Nothing comes without risk. I would say that the two largest causes of car accidents are "failure to control speed" and "failure to yield right of way". Driver distraction will also factor in but many accidents are so avoidable. I've had my car hit by a bicyclist who wasn't paying attention to what he was doing (or he was drunk, or both); he came from 2 lanes over (at the right) and sideswiped my car (which was ahead of him in traffic).
We have to share the road regardless of whether we are in a car, a bicycle, or on foot. If a road has a posted speed limit of 30MPH but you are aware that it is a residential area (and don't have good vision of crosstraffic) then you should be driving slower.
Some teenage pedestrians play chicken with the cars, running out into traffic to cross (to see if their friends will follow) and to show that they can make the cars stop.
If they get hit, it's their own fool fault.
Airplanes seldom crash but they pose an immense threat if they fall out of the sky over a populated area. They haven't been banned. The slim risk is outweighed by the benefits.
Trains wreck too.
True.
But the trouble with cars is they haven't been around long enough for Humans to have adapted themselves to living with them.
And like most technology, transportation technology will probably continue to evolve faster than human evolution can keep up.