Which proves -- in the case of flight -- that an "unnatural" refactor can be better along certain dimensions than what nature came up with: airplanes are better in terms of average speed and payload transported by air per unit energy consumed.
The parent's point was that, for driving, the "natural" human way is still better along one relevant dimension [1]: how much sensory data is required (SDCs need a lot more).
SDC engineers would regard it as an improvement if they could get SDCs to work using only the sensory data that a human would get. The parent was saying that Uber could show superiority by similarly doing more with less.
[1] Humans also drive with coarser control over the car i.e. no direct computer interface, just gripping the wheel and pushing the pedals.