If one remote operator can supervise 10 mostly autonomous vehicles, you've gotten 90% of the economic value of full autonomy.
Source: https://www.reddit.com/r/SelfDrivingCars/comments/e8bfse/way...
The real world is full of edge cases - cameras fogging up, proximity sensors confused by ice buildup, thick fog limiting visibility, sun low on the horizon blinding the cameras, badly marked construction sites, black ice, line markers under snow, potholes, slush, contradictory traffic signs, deep puddles, worn out ruts, suicidal wildlife, road debris, etc. etc.