a) need other and probably better sensors b) need to admit true self driving is a heck of lot more complicated. (consider all the things most drivers subconsciously handle with barely a thought that in fact a computer would have to “see,” acknowledge and compute if action is needed and possibly act on while also dealing with the multitude of other factors . They have things mistaking big obvious things and hitting them. The common analogy of a plane autopilot is apples to oranges. The sky is more or less empty: some birds, weather…but air traffic controllers work very hard to keep planes a fair distance away from each other.