Avoiding dangerous scenarios is the definition of driving safely.

This technology is still an area under active development and nobody (not even Elon!) is claiming this stuff is ready to replace a human in every possible scenario. Are you actually suggesting they should be testing the cars in scenarios that they know wouldn't be safe with the current technology? Why the fuck would they do that?

So no, I would absolutely not say they are “less prone to accidents than human drivers”.

OK... if you won't accept the company's reported data - who's data will you accept? Do you have a more reliable source that contradicts what the companies themselves have published?

to say nothing about the legality that will come up

No that's a non issue. When a human driver runs over a pedestrian/etc and causes a serious injury, if it's a civilised country and a sensible driver, then an insurance company will pay the bill. This happens about a million times a week worldwide and insurance is a well established system that people are, for the most part, happy with.

Autonomous vehicles are also covered by insurance. In fact it's another area where they're better than humans - because humans frequently fail to pay their insurance bill or even deliberately drive after they have been ordered by a judge not to drive (which obviously voids their insurance policy).

There have been debates over who will pay the insurance premium, but that seems pretty silly to me. Obviously the human who ordered the car to drive them somewhere will have to pay for all costs involved in the drive. And part of that will be insurance.