>What makes you think this will be close to 90%? Unless these cards are expensive I don't see that happening.

its obviously just an illustrative guess. but if the penalty of possessing the card is similar to underage possession of alcohol/tobacco, and larger penalties if a store/person is found providing a card to someone underage, i see no reason why it wouldnt have a similar success rate as alcohol/tobacco.

Why possess the card when you can just buy the UUID on the dark web

If they have access to the "dark web" they can already do anything that requires age verification there. In the same way you expect that the rule to "not sell UUIDs" wouldn't be respected there, I wouldn't expect other age-verification rules to be respected, no matter the verification method.

Well, it's rather harder to sell bottles of beer on the dark web than short text strings.

That is true, it is harder, although AFAIK people do sell all kinds of illegal things there.

sure? i feel like i need to reemphasize the "not going for 100% effectiveness" thing again.

hopefully some parent steps in if their kid is on the dark web trying to make purchases with their parent's credit card.

Well, yeah, I would just give them my code.

Why buy a UUID when you can just get porn on the dark web

Kids can buy drugs on the dark web too.