And all of those miles are in the arid southwest in places that don't have winter. They don't really extrapolate to the rest of the country or world. SF + Arizona is easy mode for autonomous driving.
Edit to add this link to some footage: https://twitter.com/dmitri_dolgov/status/1489318507342807041
[1] https://www.americanrallyassociation.org/
I've always said that self-crashing cars will win my stamp of approval when they can compete in stage rally. It'd likely push the Waymo team to evolve even further by getting involved in something like that, even with just the basics.