It appears that passkeys are now supported for Apple IDs, but only if you have the first beta for iOS 17 (or iPadOS 17 or macOS Sonoma). Beta users of Apple’s operating systems then have the ability to sign in anywhere that supports signing in with your Apple ID — covering not only Apple.com and icloud.com, but also anywhere else your Apple account is linked to — sans passwords, using just the biometrics on their iPhone or MacBook and a dream.
It works anywhere that supports signing in…
