FIDO Alliance publishes new spec to let users move passkeys across providers

Something that is not clear to me about passkeys and makes me uneasy to start using them:

Are passkeys replacing passwords, 2FA, or both?

What if I created a passkey on some device, lost that device, and my passkeys aren't cloud-backed-up? Would I be able to recover my account, or it's doomed? Or does it depend on how a given website implemented it?

If the passkey is all you have, then you're doomed (at least to the extent of whatever alternative recovery procedures the vendor is making available to you). That's why it's pretty universal to provide backup codes to put in your safe when setting up a passkey.