Passwords will never be supplanted? As always, it's a false dichotomy. Passwords will continue to be useful for some scenarios, but in others they will and are being replaced by other methods such as biometrics, U2F tokens, etc
Biometrics should never serve as a password. It may serve as a login.
Passwords should be easy to retire and change if they are compromised. You can' easily change your fingerprint or iris circle on demand, if somebody makes a good enough copy.
