"Electronic handbrakes still need a button that lets you put them on / take them off."
Have you investigated how to release it if it fails?
I did that a while ago before I bought my current car. It involved breaking into a weather-proofed sealed unit and unwinding some humongous number of turns with a special tool from the toolkit. Because you'd now broken the weather-proofing you then had to get the whole expensive unit replaced. And good luck with keeping the car in place whilst unwinding it if you were parked on a hill.
I bought something else.