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.
Winter and snow is hard for a lot of reasons. But we did some testing with safety drivers in NYC last year and will be in Buffalo this year: https://twitter.com/Waymo/status/1721629316625093035 (and others historically).
Ever think about partnering with ARA [1] (and/or Subaru) when it comes to winter/snow and inclement-condition driving? There are groups like Team O'Neil [2] up in NH that offer closed courses for challenging driving conditions, and it would likely be a cool marketing opportunity for Waymo.
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.
Next time you should try in NYC and Buffalo (or Minneapolis) during winter. Doing it without snow like the twitter and blog post show doesn't change much. Good luck.