Steven Universe as show is usually interpreted by the fandom and those who study media through queer or LGBT+ lens. This is because the creator of the series is openly LGBT+ and she considered important from the start to include these themes in her show.
However, one type of reading that i think it gets overlooked is Steven Universe as an story of immigration and growing up being mixed race that it gets represented through the protagonist Steven. I think this is because this type of reading requires a bit of extra analysis, to look a bit deeper in the show in contrast to the LGBT+ themes that are more in front.
Discussing this can be quite messy since it is loose through the series in some ways, so i would like to stay with this idea for my analysis: Homeworld and Earth could be compared to two ¨countries¨. I would be referring to Earth/human culture as the ¨dominant culture¨ while gem culture as a ¨minority culture¨ to make things more easier to understand.
Homeworld would be a country that has this totalitarianism system that tries to get rid of any people that go against the rules or try question them. It is a very scary and harsh regime to live under, which makes its inhabitants try to find a way to escape and start living in a place where there is more ¨freedom¨
So the gems move to Earth, which is this country where gems can live freely and not have to follow Homeworld's rules. They can be themselves and whoever they want to. Earth represents a sort of ¨safe heaven paradise¨ for the gems, or at least a place they can leave at peace.
With this in context, Steven can be read as a kid who is race mixed or culture mixed since he is half human and half gem. In spite of being an hybrid, he still belongs to two different cultures, which again are human culture and gem culture. He is the son of an immigrant (Rose Quartz) and one who belongs to the dominant culture (Greg)
Through out the show Steven is mainly exposed to and raised in gem culture- he spends most of his time being around the Crystal Gems by either training or going on missions with them. A lot of gem stuff is can be very messed up that the gems often try to hide certain things away from Steven to protect him from it.
Because of his mother's (Rose Quartz) legacy, there are quite a lot of things related to gem culture that end up being traumatic for Steven, either by learning about it or being exposed to them. In a way Steven dealing with Rose's legacy could be interpreted to be generational trauma that comes from being a child of immigrants that come from a country with totalitarian regime. It isn't rare for kids in this type of situation to be ¨passed down¨ their parents trauma even if their own parents didn't intent to.
Another good point that Steven grows very apart from his human cultural side, something that it is a problem because the human culture is the dominant one in the place he lives. He doesn't go to school like other kids do because of his powers- he barely has any friends of his age and interactions with other teens. It goes to the point that Steven didn't know that he had a human side of his family nor what his real human family last name was.
By the time he is a young adult, Steven has developed C-PTSD because of certain things he was exposed from gem culture and the whole legacy he inherited. He feels alienated from other humans who are around his age because he can't exactly relate to them and wasn't properly integrated or taught better about human culture.
This is explored well in the episode ¨Bismuth Casual¨ that he keeps trying to start simple conversations with Connie's school friends but he doesn't know what to say. He feels like a stranger around them and thinks that he is making Connie look bad in front of them.
Being an mixed cultural is also why Steven struggles so much asking for him from others in Future- humans and gems can't fully relate to his very specific experience of being a human-gem hybrid, more considering that he is the first of his kind to exist. There isn't anyone like him on Earth nor Homeworld.
White Diamond: ¨Half a Diamond, half a creature of earth, in all the universe there's no one else that could know what you’re going through, so maybe it's time you talked to yourself.¨
It is a complicated situation, almost existential, to know there is only one like you and nobody else can fully grasp what it is like to be you or your unique experiences.
By the end of Future Steven decides to go on a ¨tour trip¨ to visit different places around the country and catch up with some of his friends. He implies that he is probably could find a place to settle down if he feels comfortable, giving the idea that he could move out from Beach City either for a while or permanently.
The ending song from the Future and the series as whole is ¨Being Human¨, which fits that Steven's conclusion isn't only just to do a road trip to find himself and take a break from gem stuff but it is part about him learning more about his human culture and, as the song says, learning how to be ¨human¨. He is finally reconnecting with that part of his culture he always felt alienated from and finding where he fits in these two worlds he is part of.
