One critic I saw of season four of Buffy is that life of Buffy as the Sunnydale UC or whatever is not as vibrant, in its details and everything, as it was the old day-to-day routine at the Sunnydale High School.
I don't agree with it, or better, I don't agree that it's necessary a bad thing.
First of all: there are lots of episodes in this season that deal with the fact that now Buffy is a college student with college student problems.
There is The Freshmen, obviously, that deal with the isolation of being away from home from the first time (if you exclude that time Buffy ran away as a trauma reaction/feeling rejected by her mother not without reason, hardly a happy time in her life), there is the roomates issue, there is the difficult but also the excitement of choosing which courses to pick and follow and build your own curriculum, there is Willow, former nerd and homegirl in high school, who now apways want to party seemingly knowing lots of people suddenly due to her partecipation to extra-curricukars activities and such, while Buffy feels left alone, there are lots of subjects that seem more interesting that the basic stuff you were taught in high school but after all the excitement died and it's just another bunch if stuff to study before the exams, there is Buffy sleeping during lectures in the morning and worrying about passing the exams of a strict professor, there are fuckboys trying to get in bed with young freshmen girls, there is Buffy trying alcohol for the first time now that she is without adult supervision, there is the fact that she doesn't have to justify to her mother or Giles everything she does anymore because she live on her own (well, with Willow, who is also a barely adult like her tho) and this makes her life both easier and scarier (just like it is growing up)... There is also Giles that feel useless now that Buffy is at college and sesmingly indipendent and Xander who is the only one of their old trio to not going to college and living with his parents and so he feel left out.
All these are very specific "moving away to college" feelings and vibes that I think were present in Buffy's life as it was shown and were incorporated well enough in the first part of the season.
Now, one could say that most of the students, professor (woth the exception of Walsh, obviously) and the day-to-day routine of Buffy's college life are not as present as all those things were during the High School years.
But I would say that... it makes sense?
When you are a kid in school, the hierarchy and social gossip and day-to-day struggles that exhist in school are such an important (abd sometimes sufficating) part of your life and they seem SUCH a priority. Even if in the biggest scheme of things they don't matter that much! Buffy had bigger things to worry about in High School, with her mission to save the world and her fraught issues with her mother and her absent father and her biyfriend turned evil and all the death and grief and her Slayer's responsabilities, and yet when she was socially isolated at school because Cordelia told everyone she was a freak in season one, or when Snyder picked on her and told others teachers she was a delinquent, or everytime she failed or fear to fail a history text, it seemed like the worst tragedy ever!
Because she was still a kid and that's how most kids see things that happen a school, the place when they spend most hours in their life while awake. Everything seem a very big and very important even if through an adult's eyes those stuff (like the lack of popularity or a bad grade in a text or a teacher being mean to you unfairly) seem and are very inifluental.
The whole reasons why there are so many "high schooler save the world and then have to do a math text" type of stories/franchise like Buffy; and why these type of stories work so well; is that for your average high schooler those things hold the same emotional weight, more or less.
I am not saying that all of this goes away in college/university and that in a fews months you start being at barely eighteen an adult with adult priorities, but it's a slow process of realizing that the place where you study/work doesn't completely define your life, that you can and are allowed to have a life out of it, that you are at school/college to study and advance your education and everything else is an optional, that popularity is meaningless and there are bigger things to worry about, that you can cultivate friends in many unconventional ways even outside of the place you study, that the opinions of your peers doesn't define you and that you need to learn to bilanciate your social life and your home life and eventually your romantic life and everyone's life has multiple sides to it and multiple places in which it happens ans responsabilities and fun can cohexist.
Like when I went to High School MY High School- both the building and the microchosm of people and rules exhisting in it- was its own character in my life. And it was probably THE biggest part of my life.
When I started university, university was... another thing I do? Important, of course, but not the absolute center of my social and especially *emotional* life.
I know it's different from everyone, of course, but I know many people-myself included-that have not socialized with anyone they go to class with in uni and still have a good and satisfaing social life. In the same way you can not be friends with your colleagues at the part-time job you do but that doesn't mean you are friendless, obviously.
When you are still a kid, on the other hand, being a social paria in your class/school mostly equivale to being friendless, or at least it feels like it.
I think it's because teenagers tend are very very dependent they spend most of the time/socialize with most people, be it a school or a sport gym or whatever. Teens years are the year in which we start to think as the place where we spend most time outside of home as the place when we are, for better or worse, our "true" selves. The years in which every kid distance themselves emotionally from theirs parents/family and start to over-identify their selves with the image they projected amongst theirs peers, not only with what theirs parents think of them. (For better or worse).
So social life start becoming (at least temporary) more important than your home life, and most of your social life happens in one place, which, due to the limitated autonomy of movement and knowledge that teens have, is school. High school specifically. That's WHY there are so many media and tales and stories set in High School. Because it's the most basic and logic setting for a coming-of-age narrative.
While in your twenties, whenever you study or work or both, your place of studies/work is just A thing important in your life, not ALL your life.
Of course you can also set a coming-of-age story in college (in many ways, I'd say, you could write a more complete coming-of-age story post-graduation) but it would be a different, more mature story. That's why the mid-laters seasons of Buffy features college but are more about Buffy (and her friends) discovering things about themselves and the world they live into, with college as a background, while the first three seasons the monster were both about surviving high schools and surviving real life horrors, set on the same level- because that's how Buffy, being still a kid like her friends and many of her show's audience in the 90s, perceived all of it.
So it makes sense that while college as a whole is an important part of Buffy growing up, Buffy's little annoying details of her day-to-day life in school and its struggles and wonders start to becoming less and less important once the serie, the protagonist and the audience all started to grow older, and things like not passing a text or being popular or not popolar amonst your peers lose narrative importance to others, bigger, emotional and pratical struggles.