I think the reason trucks are so huge these days is not the ride feel. It's the EPA gives more lenient pollution restrictions based on size of vehicle. So instead of making the engine less polluting, just make the truck bigger and keep the same engine. It's like a cereal box that's only 1/3 full.
And you can expense a >6000lb vehicle
I believe it's a mix of both.
https://en.wikipedia.org/wiki/SUV#United_States
The idea to introduce light trucks in passenger-car shape to get around pollution limits was the car manufacturers' idea. However, the US public ran with it and bought because of the perceived higher safety and social status that comes with driving a larger, heavier vehicle than everyone else. And they continue to buy to attempt to one-up each other even though the pollution limits now apply to SUVs as well as smaller passenger cars.