We already have that, and it has solved absolutely nothing while potentially making online surveillance and privacy issues worse.

The answer isn't age-gating or ID verification, it's changing how the sites themselves operate. Get rid of the idea of "driving engagement", no more stealth ads, and no corpo, media, political party, or lobbyist accounts. Hold influencers and podcasters to the same kind of standards we used to hold journalists to, where they're required to tell you when the're shilling for some kind of shady supplement company or political huckster.

You know, the kind of shit any sane species would do with this sort of tech, but when have we ever been sane?