it´s not pay sites though, no teenagers are paying for porn
In fact very few people are paying up front for porn, pretending that kids are not just going to the many pornhub clones which are ad driven is extremely unhelpful if you are really trying to do something about kids accessing porn.
If I, as an adult, want to continue to watch porn i´ll just use a vpn rather than some stupid age check system and i fully expect that the kids will all do the same or use one of the many proxies that will no doubt appear very soon.
Don´t they have technical advisors in government anymore? why are they not listening to them?