Went to mostly private schools in America and my home country and none of them were anything like this. I've seen some violence back home but not physical. Alcohol, drugs, general bad behavior etc were a much bigger problem and definitely the worst at one public school I briefly went to.

In every school I'd say like people hung out with like people. So the "popularity" would be limited to that in-group. Most of people who PG would call "nerds" had a clique of their own as far as I could tell.

Some people might have been broadly disliked though.

it's not just a US specific thing, it's a generation specific thing.

The scenarios described in the GP link is a very late 70s-80s (Gen X) thing. 90s and early 00s high-schoolers had somewhat different experiences, but they know the trope since that's what was in movies. Schools today have a different concept of a "pecking order" - it's not that nerds aren't at the bottom anymore, it's that the whole concept changed.

Physical violence is down, it's moved to emotional and psychological attacks, which can be just as bad or worse.

This is just judging from my own experience, and my kids have a very different set of circumstances then I did.

I'm from Germany, and while some aspects of it might be US-specific, the concept generally isn't.

Sorry, bullshit. This is the basic human experience in any social group. I'm not American either and this is a universal experience.