Since I was always on the outside of every group through Junior High and High School, I never saw what you describe. But, thinking back at how the various cliques acted I do not doubt that the same thing was happening all around me while I was both too introverted and too much of a nerd to be aware.
I have no idea how I would have reacted at 13–17. I can hope I would have been someone who at the least didn’t participate or in the best case acted as a protector. But I genuinely fear that as a teen I would have been one of the abusers since I was never in that position I will never be able to know.
But based on the chance that I would have been one, I apologize for what I probably would have done if given an opportunity. It makes me sick to think of the things that were considered normal during the 1970s and 1980s, things that we are still paying for as a society.