Well there are technical solutions for this: blind signatures.
I could generate my own key, have the government blind sign it upon verifying my identity, and then use my key to prove I'm an adult citizen, without anyone (even the signing government) know which key is mine.
Any veryfying entity just need to know the government public key and check it signed my key.
I could generate my own key, have the government blind sign it upon verifying my identity, and then use my key to prove I'm an adult citizen, without anyone (even the signing government) know which key is mine.
Any veryfying entity just need to know the government public key and check it signed my key.