in which other users were systematically instructed to make sacrifices for the benifet of Google cars

I agree, but this is only one possible scenario. It is also likely that a fleet of Google cars would benefit the overall traffic patterns by routing them away from congested areas. In such a way, even giving priority to Google cars might provide an overall benefit to regular drivers, due to reduced congestion.

In any case, my point was less about the current implementation of Google Maps and more about the possibility that combining tools can lead to parasitic agentization.