And being held responsible for 4000 deaths a year is no problem for companies you mean? Exactly how is that business model gonna work? Or do you expect laws to change to assume self driving cars are flawless and always without blame? Or the "driver", which has nothing to do with the cars actions, would still be responsible?
That is not gonna work outside the US. At least in my country, even if you kill yourself in your car, it will be decided who was to blame for the crash, in court if needed. I do not expect that to change anytime soon.
We might end up where driving your own car is regarded as unsafe and even unlawful, I do not refute that, on the contrary. But, cars and the traffic situation involved, and the risks to your fellow man while operating a car is a lot more complicated than self driving trains, airplanes and boats. I expect those forms of transportation to become autonomous before cars do (on a large scale), and that is purely down to math! What airline wouldn't want pilotless aircrafts? Can you imagine the money involved if a company got software to power autonomous planes approved? That company could easily outperform Apple!
For now, the autonomous part of cars will only be just like cruise control was years ago, a luxury assistive system in expensive cars that eventually trickle down to less expensive cars, but the person in the seat behind the wheel will still be in charge and to blame for anything that happens.
How did insurance and the legal system change to accommodate all other safety features of cars? Seat belts, Airbag, ABS, ESP, auto brake. All those features saves even more lives every year than autonomous cars will (according to your calculations) but I still don't see older cars without them being heavily taxed or get prohibitive high insurance costs. Compared to autonomous cars, those systems are vastly less complicated and easy to approve of, yet there has not been any action to get rid of older cars.
According to wikipedia, the situation in the US is (EU require all those systems since 2015):
In March 2016, the
National Highway Traffic Safety Administration (NHTSA) and the
Insurance Institute for Highway Safety announced the manufacturers of 99% of U.S. automobiles had agreed to include automatic emergency braking systems as a standard feature on virtually all new cars sold in the U.S. by 2022.
The first cars that introduced auto brake was the likes of Mercedes, in 2002-2003. That means that it took 19-20 years to get 99% of the auto makers to implement auto brake on almost all cars, a system quite a lot simpler than autonomous cars and it should be a no-brainer to just require it, yet, it takes many years.
So, even if a fully functional and 100% safe autonomous car came out today, we might not see it in "virtually all" cars from 99% of the makers until 2037 and that is not considering the changes needed in the legal systems.