I think instead of flirting with this absurd fantasy of self-driving cars we should be doing more to invest in railroads and other forms of mass transit so that people don't need to drive at all. Europe and Asia are far ahead of North America in this regard.
I'm a transit advocate, but there are some fundamental issues that need to be resolved first, especially in North America.
Of course it is trivially true that we all intend to go from point A to B. But that is almost irrelevant. It is the million micro-decisions on the trip that count.
Without seeing the human, I assess in seconds whether the other driver is unusually high or low-skills, focused or distracted or impaired, polite or rude... and this constant assessment, with human understanding, of (others') human goals and attitudes is a key element of driving skills, and yes this is basically all covered in your exception of needing to account for stupidity of people. That exception is just bigger than you think.