For now, the vehicles are still the most dangerous way to travel, when compared to the train and airplane. There are always some drivers they are not really reliable. Maybe they are just careless, they are drunk or just because they are not really good at driving. If you meet the emergency situations, an experienced driver may take some special actions to avoid accident. But these things are too “strange” and difficult to handle because of the unpredictability of these careless drivers.
So in conclusion, if you want to have the autonomous vehicles and human driving vehicles together on the road, the human drivers must also change a little bit and reach a higher level.
That’s another challenge may make the driver license harder to get.