This likely isn't a selfless move, If the auto maker takes responsibility they expect to make a profit off that liability.
>Really, who else could be liable?
those who provide the map, the maintenance, the inspections, the tires, the route... So all of those will need to be provided by someone willing to take the liability. So basically Google or Volvo will likely require they are paid to provide all of these processes. Of course not all directly, but they will be the authority, that certifies those allowed to provide all of these services. Fixed the car yourself, your responsible. Wait how do we prove that, well we justified DRM on every component by taking responsibility.
This is probably the best route, even with the obvious down sides. I for one hope their is a reasonable way to get a developers license to be able to get affordable insurance, yet still be able to make modifications. (For things like adapting the tech to new vehicles/functions like offroad applications, not triciking the car into going faster...)