I graduated HS in 2000 and never really saw more than a very small handful of people wear JNCOs. I’m in northern Virginia though so maybe they just weren’t as popular around here. Didn’t see any JNCOs up in the Toronto area either.
I graduated in 2005, and by then bell bottoms on girls were back in fashion; they didn't quite hit the ground, there was just a little bit of the sole of her tennis shoe and a bit of toe visible. I kinda liked that look, then we went with 20 years of "heat shrink that ends an inch above the ankle" for some reason.
I just asked my wife who graduated 2001. She says they were popular late middle school/early HS which would have been like 96–98. I was in Canada at that time so makes sense I wouldn’t have noticed.
I remember the bell bottoms coming back. Big fan of the 2000s remix version.
Same age. In NYC it was skaters and ravers. I'd imagine any major metro is going to have more counter culture people. Especially back then vs now, when culture didn't have the same Internet pathways to diffuse so quickly geographically.