"But you can fit a full sheet of plywood on a truck bed! That's why I need a Ford F-150!"

Yea, you could do that with a 90's Toyota Hilux too and it was 75% smaller =)

Also you can fit that exact same sheet in a van and it's covered from the elements, along with your tools.

It's all about image.

Americans think van = "free candy child molester" or "FBI stakeout" and minivan = "soccer mom", which is bad for some reason.

Thus, everybody drives HUGE TRUCKS or SUVs, because they've been marketed as cool for 20+ years. Even though a proper mini van would do the exact same thing in a smaller, more efficient package.

(also huge trucks are exempt from environmental standards because of a legal fuckup they refuse to fix and thus better profits for the manufacturer)

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.

Diesel trucks tow heavy equipment (10k+ lbs) very fuel efficiently which is a common use-case in the states without needing to resort to a semi. Where I live a large number of people also own travel trailers and boats, which also lend themselves to diesel pickups.

I own a smaller truck myself (Ford Maverick) and tow a ~3000lb trailer with it regularly in the summer. My fuel economy goes from 30 mpg -> 11 mpg while towing. If I had a diesel, it would have virtually zero impact on mpg.

My take: it’s actually really awful trying to tow a trailer through the mountains without a diesel pickup.

Now, most people aren’t doing that every day, every year or ever, but a person thinks “what if I ever need to tow my airstream through the Rockies like they show on those commercials?” And they buy the vehicle with the most utility.

Other places that have mountainous regions, like South America, do have a lot more diesel trucks and 4x4s, so geographic region does play a part.