People have been hit and killed by human drivers at much, much higher rates than SDCs. Those aren't hiccups, and those are deaths that shouldn't have happened, as well. The miles driven per collision ratio between humans and SDCs aren't even comparable. Human drivers are an order of magnitude more dangerous, and there's an order of magnitude more human drivers than SDCs in the cities where these fleets are deployed.
By your logic, you should agree that we should be revoking licenses and removing human drivers from the equation, because people are far more dangerous than SDCs are. If we can't drive safely without killing people, then we shouldn't be licensing people to drive, right?