operated manually under any circumstances

What gives me the creeps about this stuff is the "Why would you want a human doing anything?" mindset. Oh, I don't know. How about if a family is on the highway merrily going along but the car's AI sees a gigantic billboard of a ad car on the other side of a river.

The AI quickly verves off the road towards the "road" of the billboard. The poor family is going to be sent flying off the roadway into the river. And there's nothing they can do. It's even more likely they'll face certain death because - as a bonus - it's 100% impossible to open the car windows or doors underwater. Car functionality was never tested underwater. Why would it be? The car will never be underwater.