In the 60's, it was comic books.
In the 80's it was movies and music
Since 2000 (actually, a few years prior), they've blamed video games.
I guess that means comics, movies, and music are okay now. 😉
Discussion
You forgot Dungeons & Dragons 😂
I thought about listing it, but i wasn't sure if that started in the 70's or 80's, and it was a bit more niche, instead of mainstream.
Another point to add, is that I've seen stats that violence amongst youth in the US has been on a steady decline since the 60's.