Let's be realistic. Self-driving cars are coming, but it is going to be a gradual transition. We've already seen the beginning of it with adaptive cruise control and self-parking. These features will continue to be refined while new ones are added, but we almost certainly face years (decades?) of gradual transition where our cars are some weird hodgepodge of self driving and user operated.
What's funny is this whole bit about "Where is my flying car?" when realistically it won't happen in any quantity until personal flying is almost completely automated. And I don't see that happening until we CAN, at least, make reliable automated cars.
The collision-avoidance problem, in some ways, is multiplied in the air. At least on the ground you have specific lanes with traffic control devices on them (lights, etc.).