@anthropy Thanks for the polite reply.I am not talking about infering age through data. I am talking about using Zero-Knowledge proofs (like ZK-SNARKS, but there are others) paired with a digital ID system (the government already know your age, so no new information is required) to generate a proof (can be a QR code for example). This code contains the proof thatYou have a digital ID account with X governmentYou are 18+It contains no PII whatsoever. The gov just knows that you generated a proof, but not where you used said proof. The website knows who issued the proof, that you're 18+, but doesn't know anything else about you.This requires zero third-party, so the risk of tracking is reduced greatly, and cybersecurity-wise it's much better than gathering a ton of information and giving them to third parties.
R