Of course, there are many caveats to comparing disengagement rates. These are self-reported by companies, and each company may have different policies about which disengagements are serious enough to report. Also, not all miles are equal. Cruise likes to emphasize that its SF miles are more difficult than Waymo's more suburban Mountain View miles.
Here's a nice summary of the 2017 data I found for you: https://thelastdriverlicenseholder.com/2018/02/01/disengagem...