Passkeys really aren't biometric authentication per se. If you use TouchID, for instance, Google isn't authenticating you based on your fingerprint. Rather, the

Passkeys really aren't biometric authentication per se. If you use TouchID, for instance, Google isn't authenticating you based on your fingerprint. Rather, the fingerprint merely unlocks the cryptographic key pair that's then used to authenticate you. I use Yubico Security Keys myself as passkeys. They're protected by a 6-digit PIN. But that PIN is strictly local to the device, meant to prevent snoops from logging in just by having physical access to the device (the keys get blown away after 10 consecutive unsuccessful PIN attempts). When I enter the PIN, the keys unlock, and it's those keys that get me into my Google account.