[snackbroken]

Ah, so it does leak your identity through the timing side channel. In other words, your anonymity is only dependent on the govt not coordinating with service providers to de-anonymize users. I assumed the 2fa app just held cryptographic keys and did some 0kp magic to show that the cert belongs to a government-attested adult. Phoning home all the time makes it trivial for the government to abuse people's privacy; they can just compel service providers to provide logs of logins.

[Mashimo]

Well right now THAT service does not even exist. The SSO exist, the anonymous age verification was an idea from another user here. Instead of sending (face)data to a private 3rd party.

[snackbroken]

My general point is that you can have anonymity or you can prevent ID spoofing, but the two are mutually exclusive.