The thing is I'm often looking at other drivers and when driving pedestrians look at me. You can send them across a crosswalk you are stopped at in a car with a wave or a tilt of your head. You can tell that person isn't going to cross the street and is waiting for a ride because they are looking at their phone and then cars. Sometimes pedestrians wave me though when I'm in my car. I had a situation where an adult waved me across at an intersection but her kids kept going. I stopped, kids stopped after mom told them to and we were back to square one of our intersection dance. Things that sensors are going to have a hard time doing.
I think we'll get driver assisted as sensors can look 360 and further ahead. highways and less dense areas seem ideal for self driving.