If you lump them all together you will mask the fact that some of them are done way better and safer than others.

I tested a cruise by moving off the curb into a parking spot at big speed. The autonomous control saw me, predicted my trajectory and slowed so it could stop if needed. The safety driver didn’t see me at all. (Safer than huma) But the uber autonomous car didn’t work like that (not safe), Tesla regularly run down children in controlled test. (Obviously not safe)

Lumping them together will mess up your statistics.