"It may do the wrong thing at the worst time, so you must always keep your hands on the wheel and pay extra attention to the road"
The car did the wrong thing but fortunately not at the worst time. I don't see how you can be so confident that there wouldn't have been a collision if it was at the worst time? It should be obvious that a car that does the wrong thing at the worst time is not safe when driven by someone not holding the steering wheel correctly.
I'm not disagreeing that he was being careless. But at what point are you going to hand the car over to drivers like him? Tesla apparently are confident enough that they are doing this now. I'm not saying they are right, but if they are not right, then when should they do this? "When the car is reliable" isnt an answer, since it cannot be made reliable for bad drivers without testing it with bad drivers.