Google, as one example, uses a bunch of information including profile information and behavioural data in sophiticated ML to imply demographics [1]. This is what I mean when I said they already do it.

The suggestion I'm talking about doesn't "solve" the adult content issue. It's more targeted at social media, which I think is the bigger problem. If it's illegal to show minors ads and advertisers can't target minors then you've just removed the economic incentives.

Youtube tends to be included in age verification legislation. Personally, I would be happy if you simply limited advertising and (IMHO) you dind't show commetns.

Roblox I think is on the right path here, at least in theory. Roblox segments users such that you can only interact with people one segment above or below you. The issue with social media (again, IMHO) is in big part that minors can interact with adults and vice versa. Really you want more of a sandbox so people can't prety on children.

[1]: https://support.google.com/google-ads/answer/2580383?hl=en

I suspect the easiest way would be to ban advertising things designed to appeal to children, which is content-based rather than reader-based and cuts with the grain of some previous restrictions in the UK (no junk food ads on children's TV, for example, no tobacco add at all). It's intent-based and so less gamable, and would tank the value proposition of British kids online, if enforced, by lowering the CPM rate.

I'm not convinced it's a good idea, FWIW, but it would be a lot less crappy than age verification.

You assume they are a minor unless you have proof otherwise, e.g. billing information. This whole mess comes from advertising economics, which don't need to exist.

Nearly no one is buying things online anonymously with crypto currencies. ID verification is simply a non issue in a world where you actually pay for things. So start making the advertising model illegal (which it should be for its price dumping market distorting effects anyway).