Ground clearance and 4-wheel drive mostly. Depending on where you live in the US, the scope of non-paved surfaces you may need to drive on occasionally can be quite a bit larger than most of the developed world. I used to have a cheap second car, a full-size 4WD Bronco, that I used for purposes that might require it when I lived in the US mountain west. During winter or when going over some unpaved mountain passes, I'd use the Bronco. In some areas even a good high-clearance AWD like a Subaru was taking a risk. Many people don't need it and most people don't need it all the time, but when you need it you need it.
There are well over a million miles of unpaved roads and highways in the US. These usually have insufficient traffic to justify the cost of putting in a proper road bed. Equally, if you do get stuck out there because of poor road conditions, you may be stranded for a long time. American trucks, for good or ill, are designed to drive on these kinds of roads all day without falling apart.
I have a high-clearance AWD today and have a lot of experience driving on these types of roads. There are still occasional times when I "nope"-out of a road and turn around due to road conditions that really recommend a proper 4WD truck. It has happened in more parts of the US than I think people expect.
EDIT: Another common use case in some parts of the US is towing heavy things like boats, in places where every other person seems to own boats or other types of large vehicle trailers. Never my use case though.