The automatic cars fails at the fundermentals of the problem.
The problem is not driverless cars. It's not drivers. It's not automation.
It's having an "on rails" system for the vehicle. We don't have one currently. Converting to it is too expensive.
All these questions and ethics were asked and solutions (to a degree) found when the first cars appeared. The answer? Get people off the roads.
Now, the option may appear again, with people having to use bridges/crossing areas, pedestrians kept at a distance from roads etc. Such infrastructure change would not be cheap, and is comparable to trams/trains.