Passwords are personal data, faces and fingerprints are not, apparently.
The rulings you're referring to are based on the Fifth Amendment. They don't involve the privacy rights of the Fourth Amendment. Rather, they treat the act of revealing your password as testimonial: if you say "my password is hunter2", you are testifying; and the Fifth Amendment says you cannot be forced to testify against yourself; so you cannot be forced to reveal your password.
You can scan your fingerprint or face without speaking a word, so those acts are not testimonial, and forcing you to do them would not implicate the Fifth Amendment. Similarly, brute forcing your password, or searching for it written down in your notes, would not implicate the Fifth Amendment.
(One might argue that breaking your door without due process of law would be a Fifth Amendment violation. I have no idea what existing precedent says about that.)
Depending on your version and flavour of Android you may need to enable this "Show Lockdown Option" in your settings.
[1] Opening this varies - my pixel is power + vol up, some phones are hold power, etc.