Well they could do it the right way where, for example, you go to your city hall to get a certificate of age where they check your ID. Then some cryptography happens so you only enter a public key from that certificate on a website or OS to verify your age.
The website or OS doesn’t check your ID. City hall doesn’t know your browsing history.
But I’m not fooling myself, that’s not the point of such a law.
Well, cars suck and 1million would be nice but still won’t but me a home where I live.