What is your definition of "average driver"? There are ~250M drivers in the US and a little over 2 million car accidents that result in injuries every year. So the average driver is doing perfectly fine. In fact 99% of them are fine. Car accidents don't follow a bell curve. If you want to make the roads safer you need to target the bottom 1% of drivers, but there is no guarantee that they are the ones who will adopt autopilot. If everyone else takes their eyes off the road it will actually make things worse.