I will admit i am arm chair designing something i have not considered deeply but all your edge cases sound like solvable problems to me and if they aren’t just not a situation to use this particular solution for. E.g biometrics on phones, open the phone for a configurable set amount of time and have fallbacks when biometrics fail (the pin) and emergency overrides for critical functionality like 911 calls. I was not proposing this be rolled out to all guns tomorrow by law but i am equally skeptical it is an intractable problem given some real world design thinking. Or constrain the problem to home defense weapons but not rugged backcountry hunting.