You basically suggesting Google to give up their(only?) leverage. Open source is all good, but if they can't make money out of these projects, you will see less of moon shots.
This seems like the kind of domain where the government can be useful. Negotiate terms to buy the aggregate data off everyone experimenting with self-driving vehicles and make it all publicly available for them all to use. Its a safety issue more than anything else, because we have borderline genocide going on every year with tens of thousands of roadside deaths, making cars safer is not just some side project for profits sake alone.
Why should the tax-payers subsidize private actor's R&D? I'm sure Google is amenable to partnership/sharing their data with anyone for the right amount or under the right terms; free hand of the market and all - no need for government "meddling".
Because this data is a matter of survival, where you can easily forecast at least several million vehicular fatalities in the next decade worldwide, it becomes relevant that the various states (I'm extending this globally since several European car companies are also engaged in automation development) it is paramount it be made accessible in the same way we seem to be finally having the epiphany that should have happened at least two decades ago that scientific research should be made openly available.
You make it sound like it is such a travesty or a great injustice, and I cannot for the life of me figure out why. Generating this data is not rocket science; it is fairly well-documented, the components are commodities and the process repeatable, one of the big challenges is that it is capital-intensive to scale. If the data is valuable as you postulate, raising the required capital should be easy, capitalism has been solving this problem for centuries.
> Because this data is a matter of survival, where you can easily forecast at least several million vehicular fatalities in the next decade worldwide,
No, it really isn't a matter of survival (at nation-state level you've elevated the discussion to). There are things that kill more people than vehicular accidents, so if your angle is "saving lives", then world governments really need to step-up their health game and meaningfully fight heart disease and cancer; hell, maybe they could even buy all the pharmaceutical research data and open that up to the public while there are at it (good luck getting a good price from GSK, Pfizer et al).
Google's push to expand their Cloud offering is also showing them trying to pursue non-ad based revenue.
-- disgruntled open source dev