When I was a kid, child programming and commercials were heavily scrutinized. Now any kid can access porn, violence, and scams on the internet. That's a blight. Not age verification.
It was still the job of the parents to set the bed times etc, but at least this was something the parents could actually control.
And for pay-per-view stations with actual heavily violent or pornographic content: Yes, they were absolutely age-gated, usually via a PIN.
Im contrast, the internet is default-permit: Everyone can access everything, unless the device is specifically set up to block it. Setting up such a block has the risk of causing massive drama with your kids, and they fill probably quickly find ways to circumvent it anyway.
This is why I find the "it's the parent's responsibility" calls so hypocritical: The whole idea behind the internet is to make it as hard as possible to block things. But suddenly we expect the parents to do exactly that? How?
(All that independent of the point that the current push for age verification really seems like a disguised push for control. But that doesn't mean there isn't a real problem. Both things can be true at the same time)
Before Internet they used paper.
That does not, of course, mean that age verification laws are the appropriate solution. You could even argue that it's not a problem that kids have access to all this stuff (though I don't think I would agree with that). But you can't just hand wave it away by saying "we looked at porn on paper when we were kids". The situations are not at all the same.
Maybe porn and violence is making today's teenager behave better than those 30 years ago after all!