Google has tried and failed at commercializing similar technology in other verticals (like building environmental automation from their DC tech). The reason is actual incumbents (rightly) see the value of their position while Google comes at it as “our AI is the value, you just make dumb things”.
I expect the automakers to ship mediocre stacks that are put together by existing players like Bosch.
As an ex-Googler I would be floored if Waymo actually lands a sell-into deal with an automaker. A fully vertical taxi service is their path today because they tried and failed to sign any partnerships.