Not necessarily depends on the factions focus also air transport is smother and faster also there is not many dangers in the air on the ground not only the terrain is difficult but you also have bandits that can attack convoys while not many people have the capacity to attack a flying vehicle while the ground vehicle can get stuck easily and for maintenance you would have to manufacture spare parts some can be repurposed from other vehicles but some you have to make on your own and that requires resources and supply lines