Except you can no longer back up your private key, so you must trust a 3rd party to restore access when you lose the only allowed copy.

It seems passkeys mostly operate in the cloud, like replication across all iCloud connected devices? This seems like a major point of vulnerability for the average user.

Private key infra in crypto/web3 tends to promote best practice as offline, paper wallet, airgapped devices, etc.

I’m not familiar with passkeys. Can you back it up as a bunch of words? Does it require a third-party thing or the implementation is fully independent.