You shouldn't apply that kind of thinking to global things. Because what you end up doing is nuking library on earth - there might be a casino somewhere near there. I see your concerns, but, ultimately, parent's carving for a comfortable illusion of control is less important than child's rights. And yes, I'll repeat it again, it's not child's best interest to have their surroundings controlled and censored.
And for reference, when I was talking about my personal experience, I wasn't talking about 80's. More like mid- to late- 00's Russia. The internet was already quite a cesspool at the time, the local IRL even more so. Just I wasn't interested. Once a teen is interested in getting into the edgy stuff there is no amount of regulation can stop them.
> there might be a casino somewhere near there.
That's approximately my whole point. We have zoning laws. We have age verification laws. We have lots of ordinances about what is and isn't appropriate in public and around children and similar. You can't open a strip club across the street from a public school and I think that's a very good thing.
The vast global unfiltered internet is increasingly pervading our lives. I think it is entirely reasonable to enact minimal regulation that stems the tide with respect to a narrowly defined goal.