I was inspired by the fact that very poor truck simulator on Steam has over 24,000 positive reviews. And I thought - "Wouldn't it great to a have a very realistic heavy hauler simulator in DCS"
In this other truck simulator, you drive across Europe, but the distances are all fake etc. In a proper simulator engine this would not have to be so. You could be hauling troops, or machinery to from one real town to another real town, watch them unload. Refuel etc.
How wouldn't want to learn the start up sequence to a beast of a truck with 6x6 drive :)
There is definitely a market for it.
Edit I'm also aware there is another truck game where you drive Russian heavy trucks, its all external view only, and its more focused on getting stuck in mud, so it's not at all a simulator.