Jay @Jay - 1d
2FA: nsec + bitcoin Probably doable. Once the nsec is proven rotatable in practice.
See if you like this, Bitcoin as an authentication mechanism: You have a utxo in an address you control. A gateway, preprogrammed with that address as your identity, gives you a challenge token and you sign it with that address' keys. Or, if for whatever reason, you can't send a signed message to the gateway, it can be preprogrammed with your xpub as your identity. You obtain a challenge token and put it in a transaction that moves that utxo to the next address in your xpub, it gets mined in a block, and you obtain access via the gateway.
That's the first scenario, yes.
