So basically this whole thing is a ploy to get rid of porn: basically, censorship that vaguely tries not to look like censorship.

1. Instigate a completely impractical, rights-violating scheme for age verification that nobody in their right mind wants to implement.

2. Then, enforce it against whatever porn sites land in your jurisdiction at all, knowing that they, like everyone else, don't do the verification.

Am I close?

Suppose the porn site tries to implement it. How many people are going to hand over their personal info to a shady porn site? Most visitors are there anonymously for whatever free stuff they can watch.

Either way, the porn site is ... screwed. Implement age verification: 99% visitors now back-button out and find another porn site. Don't implement it: blocked or shut down.