I think 10-15 years is extremely pessimistic given we have cars on the road now delivering passengers. Scaling that is the game.
No we don't, only local roads, not fare-paying passengers on freeways, not in NorCal. In Phoenix AZ they are still testing self-driving on the freeway on employees, not fare-paying passengers on freeway.
Wait until you see self-driving taxis on freeway and to/from airports, with fee-paying passengers, in traffic, in bad weather, at night. See how many accidents there are per million miles. Then the discussion moves to "How many accidents/fatalities are acceptable per million passenger-miles?"
It's hard to do worse than human drivers on that front. Especially under the circumstances you mention.