[yoshuaw]

> Right now none of the Passkey syncing providers support anything like that (and I feel like they won't, because it'd be a huge vector for scams).

Within the Apple ecosystem Passkeys can be shared with contacts through AirDrop (no other methods are presently allowed). The Passkey is then copied directly from your Keychain to your contact’s Keychain.

[josephcsible]

Yep, and this is the worst of both worlds. You don't get the security benefit you would if the keys were stored in non-exportable hardware, and you also don't get the freedom to move them to a different ecosystem.