The only public data is California's safety reports over the last couple years, which show Cruise and Waymo having millions of miles driven with Waymo having fewer "disengagements" than Cruise. There is also the fact that Waymo has ride sharing service in "production". As someone who is also outside the AV industry that is the closest I've gotten to a source, everything else is just hearsay by various Hacker News engineers about how Waymo is the best.

The ranking as I understand it is Waymo, Cruise, then everyone else.