Most of the facts exposed are likely inferable anyway, or certainly were in a non-GDPR tracking world. I think it'd be clear from my browsing patterns that I'm over 18, and broad tracking + IP checks could quite easily infer where I actually live at least to a national level, I'd be confident that e.g. Meta already know this without being told. Given that, I'm not too worried about exposing residency + over-18 status, the fingerprinting bits are redundant.

Whether it's actually anonymous in practice, and/or whether it starts to go further than that (websites asking for verified gender? First name? City? Full DOB?) will be a real concern but I think there'd be plenty of push back and tech will end up setting norms here through the browser APIs & permissions prompts. In theory in this is all covered under GDPR anyway so requesting or storing information that's not necessary is illegal anyway, and at least explicit requests are less secret than invisible tracking of the same thing - much easier to reject individually, and to litigate abuse collectively.