Nope! You could have one "master recovery key", the public part loaded on your device (to be registered during account creation) and the private part sitting in your safe. Or even a number of pre-generated recovery keys. You could also give those keys a higher "priority", since they're offline, so that they can revoke lesser keys in case of account compromise.
The problem is that the passkey protocol prevents you from adding a (additional) key you don't currently control. This is what crote was referencing here:
> Passkeys have to be online to enroll additional keys, so any kind of software or smartphone solution is going to depend completely on cloud sync.
I proposed a protocol with this feature almost a decade ago: https://www.researchgate.net/publication/343318317_Privacy-a...
The problem is that the passkey protocol prevents you from adding a (additional) key you don't currently control. This is what crote was referencing here:
> Passkeys have to be online to enroll additional keys, so any kind of software or smartphone solution is going to depend completely on cloud sync.