If you were using webauthn as a second factor, I believe the passkey changes implemented by Apple and others means your device bound webauthn keys are now synch

If you were using webauthn as a second factor, I believe the passkey changes implemented by Apple and others means your device bound webauthn keys are now synchronized to their cloud services. That hurts and my enterprise had to halt their rollout of webauthn for MFA while we figure it out.