Earlier quoted context omitted.
We have had the need to prove age for hundreds of years. To buy alcohol. To drive a car. To vote. We depend on government-issued documents to do this. Not sure why anyone would really expect this to change just because it's online now.
Very obviously because privacy advocates are concerned by the effects of mass deanonymization. I find it doubtful that you don't grasp that.
There is a big difference between: Government demands every website to have age verification, and government supported scheme by which service can opt into age verification.
As of now, American private spyware is actively filling the demand.
I get the feeling some privacy advocates are approaching the choice as a tier system, with government being the worst case.
I don't see it.
The only viable solution for the future of privacy is to not be dependent on the giant platforms in the first place.