When I was a kid in the early 2000's we were vibing to a funny song about a famous pedophile, watching pictures of dead people on rotten.com and ofcourse porn on the late night tv. We also had candy resembling tobacco products as well as ones with racist names.
I think new parents especially often seem to forget all the similar things they did as a child and then apply different standards to their own kids. Yeah, it's not optimal, but they're probably going to grow up just fine.
There are multiple possible explanations for that. I don't see any direct link between the kind of content we millenials consumed in our childhood and the apparent rise in the number of mental health cases. I'd be willing to bet that the time spent consuming said content plays a much bigger factor.
At least those horrible things required human effort to make, so there was a limited quantity. An unlimited supply of content that a human had no part in making is completely new territory
It's not obvious to me why the non-human origin matters here. Eventually AI will get so good that you can't even tell the difference, or if you can, it's because it's so high quality.
In my mind the meat of the issue is the amount of time we spend watching that content, and less so who made it.
Non human origin matters because it's easy to flood the field with this stuff.
If finding quality videos becomes a needle in a haystack amidst ai generated bullshit, each looking to passively earn a few bucks, overall quality of life will suffer as the ouroboros eats its tail.