If you read many of the top selling books of the 30s and 40s they definitely had anti-heroes, they just weren't called that back then

I think people have always been caught up by the idea of being "against society's norms" and what it means.
I know my grandparents' generation talk about running around playing cowboy and indian and wanting to kill each other over and over again. So they definitely had a penchant not only for "violence" but in a far more physical manner. They weren't doing computer generated mayhem, they were actually running around and bashing each other. Schoolyard fights were fairly common. In modern times we call in the police if someone says a bad name to someone else.
I think kids back in those days were fairly accustomed to *real* blood and violence

So I'm not really sure things are "worse" in modern times, it's just that we have far higher expectations. Which I would say is a good thing ...