Majority and Minority
This is a worldbuilding post, not a politics post, though obviously there's some overlap. It's mostly written in service of understanding some of the "inherent" dynamics that might exist absent e.g. colonialism, prejudice, overt discrimination, fetishism, exoticism, historical inequality, etc.
There are a lot of ways that any minority will face problems the majority doesn't, even in the case where that disadvantage is not something that was ever intentional or rooted in prejudice.
Let's take the case of elves and humans. In this toy example, humans make up 90% of the population, and elves make up 10%. Their history is long and peaceful, and the ratio has been constant for a long time. These elves are humanoid, relatively long-lived (by a factor of let's say x2), taller but skinnier, and have some relatively subtle differences in biology. We will assume that there's relatively little difference in culture, that they all speak the same language, etc.
Services
All else being equal, we should expect that elves make up both 10% of those providing the services, and 10% of those demanding the services.
For many cases, this is perfectly fine, particularly those where there aren't differences in biology. If you need a website made for you, you wouldn't care whether an elf or human was doing it. You wouldn't care whether your janitor is elf or human, this is going to have no impact on how clean the floors are. Again, we're assuming relatively minor differences in biology, not super-elves who do everything with grace and precision.
For other cases, this isn't perfectly fine. We should assume that only 10% of doctors are elves, and depending on the total population, this means that some specialist positions will only have humans. How many urologists are there in a mid-sized city? And it almost doesn't matter whether the doctors are elf or humans, because the patients have this same 90/10 split. Assuming there's no demographic concentration, doctors get experience on elves at 10% the rate. We should then think that unless there's specific effort being made to train people in every service sector that they're simply less experienced with the elven clientele.
This applies to lots of services. If elves are taller and more slender, then what they need from a tailor is very different, right? If their hair grows differently, or is finer, then they might prefer different haircut, styles, and have unique needs from their barbers. Even relatively small differences in physiology would mean they have different demands of a personal trainer. We haven't established whether they have different diets, but it's easy to imagine even relatively small difference in preference result in worse experience overall (more on this later).
So in a society that has made no particular efforts to change these fact, we should expect that elves simply experience worse service on average than humans do. Every service they go to has less accrued experience with their demographic, if nothing else.
Goods
Humans and elves might also want different goods.
If elves are taller, they might want longer beds and longer blankets to go along with those beds. They'd want different clothes, whether or not those are made by a tailor. They would want different chairs for their longer legs, and different tables to sit at, and this is just focusing on the single aspect of height. If their hair is lighter, fingers longer, etc. there are all kinds of differences between the products that they would want and those that humans would want.
Diet is also something to consider, because it makes up a large component of consumption. If elves have slightly different preferences, like a lower spice tolerance or vegetarianism, then they're going to have a harder time finding foods that match their tastes, less selection, and a lower quality of goods at higher prices.
Goods operate on economies of scale, which means that some products would only make sense to make with humans in mind. This is especially true in the modern day, but I think was also true in medieval times, because the invention of factory processes wasn't the invention of making a lot of identical things.
So the smaller market of elves will have less selection than the larger market of humans, and in many cases craftsmen and companies will have to decide whether to make a product that works for both markets, run two different product lines, or simply abandon the elf market.
This applies to entertainment too, which is midway between good and service. A large production, like a play or a movie, will have to decide whether it's catering to elves or humans, or more likely, how much it's catering to each demographic. Obviously there's financial pressure to cater to the largest market. In our perfectly egalitarian city, perhaps this doesn't matter so much, but there are specific themes that might resonate more with elves that humans, and these won't get explored, and certain characters that humans might prefer over elves, which would show up a lot. (The less we assume a homogenous culture, the worse this would be for the elves.)
Demographic Concentration
One very natural way to combat these issues is demographic concentration. All the elves use elf services, all the human use human services. That would be at the most extreme, more likely we would see a mix. Another name for this is "ghettoization", which I've always found to be a little ... well, charged, given the history of ghettos. I'll be avoiding that term here, especially because when we talk about ghettoization it's often in the context of explicit legal and discriminatory pressures that we're assuming don't exist.
The process of demographic concentration goes like this: rather than going to a doctor who has 10% elven patients, the elves go to a doctor that only sees elven patients. This removes any kind of skill gap that's based in a lack of experience, and in that way is good.
However, a city can only support so many people of each profession, and in a mid-sized city this can mean either a lack of specialists or a lack of options. If the city is large enough to support 9 urologists, then we expect either the elves have zero or one. Zero puts them right back where they were (going to doctors who see only 10% elves), while one leaves them with a single choice.
If demographic concentration were "complete", an extreme situation where elves only went to businesses that catered to elves, then the elves would essentially have their smaller city inside the larger city, with 10% (or less) of the options and much less variety given the economies of scale. And of course there would be some businesses that simply would not exist, because they can't be supported by that small a number of people.
Demographic concentration that's geographic concentration would have even more magnified effects, and even if we started with cultures that are homogenous, heterogeneity would be likely to follow.
Society
You're an elf. You make a post on the internet about elf stuff. Who is most likely to respond to it? Well, all else being equal, it's going to be 90% humans.
You're an elf. You want to play some tabletop game and find a group. If there are less than ten people, how likely is it that you're the only elf?
You're an elf. You work in a small office. How many other elves do you expect there to be?
Now, this is not necessarily bad. We've stipulated that the elves and humans essentially share a culture, and that they're biologically close to each other, and that their society is one without any inbuilt prejudice.
But there are all kinds of situations where there's going to be some friction. You and your friends are looking for a place to eat, your office is organizing a potluck, you're trying to get at one specific element that is unique to elves and the humans are trying to offer their own experiences which suddenly makes it about a human stuff ...
How much of a problem this is definitely depends on some very specific elements of culture and differences between majority and minority. We can imagine all kinds of scenarios where this is more of and less of a problem, and scenarios where the problem is a reflexive one. Maybe an elf posts about hating cold ears in the winter, and a bunch of humans chime in that they hate it too, but the elves have longer, more sensitive ears, and it's really not the same thing, but it might feel very slightly alienating to share this thing and get what's supposed to be relating to you, but is not.
I think this one is particularly hard to gauge in the abstract.
Advanced Cases
We've been assuming that there are only humans and elves, that there's a 90/10 split, that there are no enormous biological differences, that they mostly share a culture, and that their society is egalitarian.
So what if we change those things?
Obviously every problem is amplified if the minority group is smaller. 99/1, or even 999/1, provides much different dynamics. At those ratios, it's not just that people have less experience with the minority, they might only have a single experience. A tiny minority is essentially captive to the majority's tastes and needs. An egalitarian society might accommodate them, making sure that public benches and drinking fountains and classrooms and buses and schools and libraries and city hall and prisons work for everyone. An egalitarian society with certain assumptions about the balance of public and private might have laws that require all buildings follow a code that works for everyone. But there would still be frictions and things that fall through the cracks.
If there are enormous biological differences, accommodation becomes more difficult and expensive, and less likely to be done. A restaurant that caters to elves by giving an option that humans also enjoy (for example a nice, if standard, spring salad) is reasonable. A restaurant that needs a selection of rocklike food bricks on hand is less reasonable, depending on whether they're shelf-stable. For a restaurant to hold a collection of live animals? Or perishable foods? Unlikely to happen if they're expecting that to account for a tenth of their headcount for the night.
The biological question applies to many, many, many things. One of the fantasy things I often think about is hobbits (and I might have even made a post about this), and how their size means that they have different biology, and how this impacts things like rent prices and meal prices and generally creates a lot of sociologically interesting impacts. But obviously you can get much different, you can have species that have very few meaningful points of intersection, where accommodation is not a matter of easy wins, it's difficult work that produces two (or more!) parallel sets of infrastructure if you want to do it properly.
Humans need a house that's wired up for water, can you imagine how much of a pain in the ass it would be if glorpians needed their own glorp tubes and didn't really have much to do with water?
Conclusion
This is one of those things that I think about a lot because ... I guess because I don't hear people talking about underlying structural forces too often? Because in worldbuilding terms, I think it's a very useful thing to think about, rather than always borrowing language and constructs from the real world. There are structural challenges that emerge from lopsided numbers alone. And there are solutions to those challenges that might emerge naturally, and others that might have to be pursued by policy-minded individuals.
(Just pretend that I wrote a big long caveat about how in the real world, this is one small aspect driving sociocultural forces, I really hope that this is obvious to you, the reader, and I just don't have the energy to spend five paragraphs doing defensive writing against an imagined conversation on how this analysis gives an incomplete picture of structural challenges. I know this, you know this.)
