Despite Maxwell's nonsense talk and Lindley's reaction time argument, there are many situations that cannot be avoided solely by faster reaction times. The driver needs foresight/anticipation. An AI that advanced is far away. And the idea that the computer should interpret a slam on the gas pedal as get the hell out of here command is nonsense as well, since there have been many cases where drivers hit the wrong pedal in panic. So the AI has also to properly interpret what the driver meant in a dangerous situation? Not feasible. You cannot remove the human element, and you cannot make sure that you catch all human errors. You can enhance safety with driver assistance systems, but that's all. You will never be able to remove the driver's responsibility.
You aren't impressed with the technology that you can get in a 2014 Mercedes S class? The car - for all intensive purposes - drives itself. And that tech is available today provided you have ~$92,000 to lay down on a new car.