I don't understand why what's essentially a login (fingerprint, face, dna) is considered a password. It simply isnt. And I don't understand why I cant (on Android 7) combine fingerprint and then PIN/Pattern to unlock my device. It's mind boggling and completely stupid.
Biometrics is biometrics. I like to think of it sitting between a continuum between "username" and "password".
I might like a setting to require both a Touch ID (or Face ID) and a passphrase to unlock my iPhone. However, Touch ID has flaked out enough times for me (not accepting my fingerprints) that I probably wouldn't like to risk it in practice.