How will elders get around? They'll move!
A somewhat vacuous discussion at the NYT, which you may access here, suggests that elders want to stay in their homes and assumes they will always need cars to get places. In reality, many elders are willing to move- they are, after all, no longer anchored by a job or a child's school enrollment- they just don't want to move to a place that's worse than where they are now. When elders say they want to remain in their home, they mean their home, and not a nursing home or a rental in a government "project".
The NYT "discussion" was, in fact, doubly vacuous by 'assuming' that the full panoply of support that created and maintained suburbia will remain in place long enough to make it necessary to invent automatic cars. Get a clue, people! The age of the automobile is ending, and the only real remaining question is how it ends.
Wasting tens of billions on efforts to build automatic cars is a good way to ensure that it ends badly.