I think quite often people buy pick ups and SUVs because of savvy marketing from the Big 3 using the same image used for decades to sell cigarettes. For every contractor who needs a truck for work there are probably half a dozen who never put anything in the bed of their truck. Jack it up, you rebel you!
Plausible that this "chicken/egg" situation started from OEMs telling us what to buy (if the margins justify it) but having grown up and owned some, I find it improbable.
A few factors come to mind:
1. Americans are increasingly taller and fatter; a high riding position with easy ingress w/o needing to bend much is just more comfortable. An increasingly aging populations will opt in for these.
2. Infrastructure's gone down the pit. Trucks just take pot holes more comfortably.
3. Increased cost of living and home ownership; A lot of DIY to avoid contracting or leasing costs and buying/selling of used large items and/or moving around for a cheaper rental.
4. American families are increasingly smaller; You'll fit a whole family in a crew cab.
5. Americans by and large move a lot for better jobs; refer to 3.
6. Improved fuel economy means you can get a ford maverick that gets 40 mpg.
7. Improved "carness" of trucks means you don't sacrifice much in terms of comfort, safety, features, amenities, or handling.
8. Speculative: Increasingly sold on the "influencer/social media" explorer lifestyle of going out there on an adventure.
9. Speculative: Increased migration to suburban or more rural housing where a truck is best suited for unexpected road conditions/floods/etc...
