Never thought about this before but we already have biometric scanners on our phones we rely on and work quite well, why couldn’t it work for guns?
Or you didn’t press it in the right spot?
Or the battery was dead?
If I’m out in the wild and in a situation where a bear is coming my way (actual situation that requires carrying a gun in certain locations) I do not want a fingerprint scanner deciding if I can or cannot use the gun. This is the kind of idea that only makes sense to people who have no familiarity with the real world use cases.
Facial recognition: 3D Infrared
Fingerprint: Capacitive