I see Google and Apple really embracing passkeys lately and I’m trying to understand the hype, but it can be challenging. I also see that Bitwarden and 1Password are embracing them too. As far as I can tell, passkeys are just key pairs that behave like FIDO2 tokens (e.g. my yubikey) but are backed up to some cloud and usable from multiple synchronized trusted devices. Is this accurate? How would I go about implementing a self-hosted Linux equivalent? Use it with pam? Is this just a fancy ssh-agent for other protocols? What are you all doing in the eliminating passwords space?
https://github.com/AlfioEmanueleFresta/xdg-credentials-portal is a WIP proposal for a spec to enable OS-level support for FIDO similar to how Windows and macOS do it. Not sure how far away from being approved it is, but that would then make implementations easier to build
See also https://github.com/psanford/tpm-fido