Yeah, exactly ... as more gas guzzlers are phased out, more electric cars are on the road (and the hybrids) - the revenue becomes less and less (in absolute terms) - while the roads and highways and infrastructure keeps wearing out.
One thing I just thought of: Isn’t OPEC going to throw a hissy-fit? They’ll no longer have the oil option to control the world or the US for that matter. Our region will become the world’s oil exporter.