Yeah I think there is some research showing how aircraft passengers can easily get confused about how to unfasten seat belts in an emergency situation. (Or at least that this is taken into account in the design of the seatbelts).

Your brain can switch into a very different mode in “stress” situations, especially if it’s a scenario you’ve not had repeated training for.

Even in normal circumstances having two possible ways to open the door seems… unintuitive.

Right, I agree, which is why I think there's only so much you can do. At a certain point someone is going to panic and lose all their ability to reason or see otherwise obvious things. It's an edge case.

Though I have to say, being unable to open the doors with the button doesn't seem panic-worthy. I'd be irritated at first, then intrigued, then I'd just pull the manual release and put in a service appointment to fix the car. Being unable to get out instantly is very rarely an emergency.