The entire pitch for autonomous driving is that it's safer than human drivers. If that's false it's not clear why we should continue to allow Uber to test their work on public roads.

It could be safer than human drivers and still cause quite a few deaths. We can't evaluate such statistics from one accident. We don't even know if this particular accident would have been avoided by a typical human driver (there was apparently one behind the wheel of the vehicle).

I think the world can probably stand to wait a bit of time while precisely this question is investigated.

That's reasonable while the system is in testing and in small scale use. If it ever becomes a major part of the transportation system, it won't be desirable to shut it all down every time there's an accident.

In my view, it should not become a major part of the transportation system until we are confident that it's actually safer.