Not true at all. Arma and the flashpoint series focuses on a full on combat relism enviroment that is extremely modding friendly. I can name off a hundred guys that take 3 to 4 hours in a mission(mission pending) and the 24 hour sim is very helpful or not at times. But it doese make things alot more intresting. SMALL details count whether its car doors that open or foot prints in the group or graffiti on walls in a combat zone I think it sets a real feel for the enviroment your in. Huge maps are a common request because people like them. Everyone oviously has a different view on how a combat game should be built and with the technology being developted everyday I'm fairly sure many want a really open modable enviroment to use. Think about making small maps in a big one so others may want to use the whole thing and others like yourself would be able to create small sectors to play.
PS large terrain dousnt have to be just for the long guns.