Also one funny thing is that because of the schoolgirl anime/manga thing and cosplay, there is a subculture of
gyaru called
kogyaru who have a dress code of school uniforms with short skirts. Note that they
may be students, but not necessarily so, and some of them deliberately go to schools that don't have a dress code, specifically so that they can create their own "sexy schoolgirl" cosplay uniforms.
This specific subculture use to be the biggest "gal" subculture in Japan, and it peaked in popularity at the end of the 1990s so it had a big effect on current anime styles. But it doesn't reflect much to do with official school uniforms. When you see a photo of a bunch of Japanese schoolgirls with really short skirts, you need to be aware of the kogyaru / cosplay subculture, and how they're more likely than not part of that, and not wearing an official school uniform which somehow lets you get away with a miniskirt. Or they might have deliberately hiked their skirts up for the photos.
So those anime schools would only make sense if there were schools that forced the girls to wear anime-style schoolgirl cosplay or forced them to dress as the kogyaru subculture. It would make about as much sense as having a series set in 1977 England where the school uniforms are punk-style.
EDIT: Man you have to love 2000s Gyaru culture and how it evolved.
Gangaro, Yamanba (literally the "mountain hag" look), where they tanned their skin dark and put white make-up around the eyes.
Well dark tanned skin is out now. So gyaru will lighten their skin back to normal now, right? right?
Here's a whole pintrest full of them to show that this is in fact a scene and not a one-off:
https://au.pinterest.com/shaivism/shironuri/?lp=trueModern gyaru fashion is basically a huge "fuck you" to the whole world and everything normal.