Earlier quoted context omitted.
Miles driven should go up but with far fewer vehicles, since with autonomy cars can operate almost 24/7. But point taken, we will need those autonomous cars to be BEV and use renewable power.
I have not seen automotive industry projections that predict fewer vehicles.
But in all the other NON-automotive industry sources the idea of a car that drives itself and acts as a taxi suggests 4-10 times less cars needed.