Unfortunately ZKP's aren't magic.

When not doing privacy oriented cryptocurrency (cough money laundering cough) with ZKP's, if you really want private verification you are in a position where a single actor can authenticate the entire world and no one will know it happened. And to prevent it you assemble the pieces necessary to deanonymize anyone.

Make no mistake. ZKP age verification, as proposed, will just require multiple parties to collude to figure out your identity.

They can't even implement ZKP for remote attestation due to the auth-the-world problem.