Good news. A good chunk of the world already uses crypto for identification. My eID card is just that, i can auth with a chip and pin. This is normal in a lot of the EU.
I don’t want my identity to be linked to many of those accounts. So I’ll take a yubikey. Second, I’m glad I don’t live in a country where I’m required to carry id.
You don’t have to but in situations where you are unable or unwilling to show your ID and a peace officer wants to check your identity, they’re entitled to take you to the precinct.