What kind of disabilities are we talking about? Because I’m pretty certain that to a blind person a car won’t help them much, and in fact probably makes life in general more dangerous. Further poor people who have a mobility impairment are often forced into dangerous situations, such as operating a motorized wheel chair in mixed automobile traffic instead of being able to use a dedicated bike lane (yes I’ve seen this many times).
EDIT: I'm not saying wheelchair-bound and other similar people should be banned from driving. Like today, we can add wheelchair-only parking accommodations. In fact, restricting traffic to only people with a genuine need will make their trips faster.
A bus will not drop you off right in front of a specialist clinic for your weekly appointment. Also buses are incredibly hostile for wheelchair bound people, even if they are not meant to be. Seriously try boarding a bus during rush hour on a wheelchair - the driver has to help you and people have to move to give space for you, but in general it's an unpleasant and humiliating experience(people who are usually already late are suddenly even more late because of you, and sometimes even comment on it - you need to grow some proper thick skin to not give a damn).
Besides, even if you are on a wheelchair with lower body paralysis you can still drive with hand controls.
Paratransit is recognized in North America as special transportation services for people with disabilities, often provided as a supplement to fixed-route bus and rail systems by public transit agencies.[0]
EDIT: I'm not saying wheelchair-bound and other similar people should be banned from driving. Like today, we can add wheelchair-only parking accommodations. In fact, restricting traffic to only people with a genuine need will make their trips faster.