Very simple - people who want a truck to excellently tick all the basic boxes of functionality/durability/reliability.
On the flipside you have the expat douchebag mobile called the Ford Raptor and its slightly less idiotic "-trak" trims. Standard Ranger trim is fine but Hilux probably still a better long term choice.
D-MAX, especially the lowered ones often seen in Isaan? Stands for Douche-MAX.