Jesus! Scary proposal and I wouldn't expect to to even be effective. Very bad for privacy. Credit cards are effective for verifying age. The other day a customer in my store (21+ because we sell nicotine) tried to pay with her daughter's card and my PoS declined it because the account holder was underage.
Free sites like pornhub could charge a one time $1 charge to verify age to gain entry. They could even refund the charge. Snoopy AI is not the way! How would that even work? Seems more invasive and less effective.