>US trucks are just a peculiar form of luxury car
No, not really. You can get one fully loaded, or get a bare bones work truck. Thing is there are no "luxury" makes for trucks, but more often there are trims of different models. A F-150 Raptor is certainly a luxury model for status signaling (or just to have the nicer thing for those who can afford it). The XL Model is far from a luxury vehicle.
https://www.ford.com/trucks/f150/models/