The point of a gun is that it's a simple machine that works when you need it. Geofenced microcontroller safeties somewhat compete with this and would not be a popular idea.

I’ve seen plenty of sci-fi that leads me to believe that the future of this is some sort of finger print reader on the trigger that only allows the designated shooter to shoot.

The recent incidents involved "designated shooters."

What if your adversaries have the same problem?

Also, we put our lives in the hands of tech all the time.

Or Walmart. Or churches. Or music festivals. Or your workplace, so all workplaces. Or your grandma's house.

Yes, those too. Perhaps allow guns to work only in the owner's home or around it.

Knives, too? Because I need my gun to work when someone charges at me with a knife in their hand.

Do you have a broom? Congrats, you have just established a reach advantage.