Where are those former peers now? You reference this like their life trajectory must have been irreparably harmed by it. Are they in prison? Were they killed while committing violent crime? Are they on disability from being permanently emotionally crippled? Or what?
A little tangential since this is more about gating white supremacist content than violence or sex, but I was on 4chan when it was being infiltrated by genuine white supremacist organizations and Russians that talked about how manly Assad was to influence teenagers interested in anime. I had people in real life to talk to about these things so I narrowly escaped the influence. Looking at the current state of the US, not everyone did. That being said, despite my hope that older people would be less prone to such influence, it doesn't always seem to be the case.