Comment by CaliforniaKarl

A long time ago, I'd participate in things like CAcert in-person assurance, PGP key-signing, etc.. I think a model like that would've been useful here: An AgeKey issued/signed by two people. I think of it like a decentralized equivalent to someone's parents saying "Yeah, $CHILD is old enough", or to a cashier saying "This person obviously looks old".