I'd question those figures, for humans. Per the AAA Foundation

Ok, so i am being generous to humans - the actual is far less than 1M...more like 500-600k miles between accidents (of all kinds).
Think about your drives in heavy traffic and how any stupid mistakes you see people make. Other drivers compensate for most of them, until they don’t.
I have a model Y with FSD, and about 6K miles on it, driving ~ 45 min in Dallas traffic 2x a workday. The other day, a car pulled out right in front of me (I was going about 60 Mph). They obviously didn’t see me. The car swerved and avoided the accident - it was so fast it was done before I could react myself. That probably would have been an accident had i been driving, and definitely if i had not been paying close attention.
Oh, and don’t forget about all the distracted and drunk drivers. I routinely see people looking at their cell phones in heavy traffic.