I think the people proposing these things do not understand the problem, let alone the solution. Driving in all circumstances is something that humans can find hard work sometimes. It is way beyond any technology we have now or are likely to see in the medium to distant future. There are moral choices too. Do you kill a child to save the occupants? How on earth do you build these into any conceivable machine? Who is responsible, if the guidance system goes wrong and causes a crash? The manufacturers? The Insurance company? The occupants? This is not an abstraction. It has happened.
I've been thinking about this quite a bit since you mentioned it before and sort of been putting a priority/avoidance list together. So far it goes like this ....
Avoid:-
1. A person not in a vehicle.
2. Another moving vehicle.
3. Damage to vehicle itself.
3. A building/structure.
At each of those points there is also a scale, especially number 3 where there may be a choice of actions so the priority is to enable the option that minimises the damage to the vehicle itself.
Liability could be handled by a certification system and insurance. There would be no blame for owner/manufacturer/keeper for a certified car provided it was being operated correctly, basically there would only be first person insurance - your car gets damaged then the insurance pays for it to be repaired whether your car smashed into a wall or someone else's car drove right through you.
I still think you way overate human capability for driving, many people have no idea how to handle a skid or even know when to brake. Panic is not a good conducer of safety. Our eyesight is very poor, the brain makes loads up to make up for it. It is the need for "control" that drives the arrogance that makes people think they are good drivers.