Pretty sure it was due to some regulation I think this one: https://en.wikipedia.org/wiki/Chicken_tax that made small truck imports impossible. Also due to all the safety standard requirements (no hip space nut crushing leg confinement) bigger cabs were the only way to actually fit bigger people. When vehicles advertise "leg room" its a joke what people really are looking for is hip room, front bench seats, column shifters, no center consoles, etc.

There haven't been any mid size or small vehicles with a front bench seat in over a decade. Even F150 and new Chevys are getting rid of front bench seats. F250 and large vehicles are the only ones for those of us who don't cross our legs when we sit (have nuts).