Aerodynamics as well, new cars and especially ev/hybrids are slippery compared to many/the average if we take old cars to mean 50’s through 70’s.

Does that matter much if you only drive around town at 30mph?

An older sedan-style car might still be more aerodynamic than a modern SUV, simply because the frontal surface area is smaller. The less air you have to push out of the way in the first place, the better.