Nothing against Truckers (and they pay dearly for it) but I don’t think autos and pickups have much an effect on road surfaces. It’s the big trucks and the like that trash even the interstates. Shoddy materials, installation, and lack of maintenance doesn’t help.
You are right about that. Just drive in the outside 3 and 4 lanes of a freeway and you can tell. But there are many reasons for roadway potholes and such. Cracks from tree roots causes many problems too and once water gets under the subgrade from a crack, it never dries up. As you know a tree is the same above and below ground. Pretty soon a piece of asphalt or concrete pops out and it just gets worse