The first thing you should realize is that pedestrianized spaces are really nice for traveling in a wheelchair or mobility scooter. The second thing is that there are cars available in Europe, called Cantas, that are conventional gasoline ICE cars with purposely shrunk engine displacement. You'd never take one of those on the highway, but the underpowered engines make them safe (and legal) to take on any sidewalk or bike path.

All in all, a car free space can be far better for the disabled than what we have right now.