This could apply for both air and ground sim, but im going to talk about air sim.
Why are some countries able to use various imported/captured vehicles in simulator battles? to me, it seems entirely unrealistic as well as unfair. for example, in 11.7-12.7 tier air-sim battles, germany, china, and russia can all be on the same team, while fighting nato/western countries. logically, these countries would only be able to use their own soviet or chinese jets, rather than using a subtree or imported vehicles from other countries. being in a mig-29 while almost the entire rest of your team are in vehicles like the f-18 and f-16 causes confusion, for both you and the enemy team, which results in making iff a nightmare, especially at longer ranges or in a dogfight. because of this, i think sim battles need a rework, which would only allow soviet countries to use their own jets, while nato/western countries use their own, thus eliminating confusion. if these countries were to be able to play with vehicles in a subtree, like the swiss f-18 or tornado for specifically east germany, they would have to play on the nato side, while west german mig-29s would have to fight on the soviet side.
thats all ive got, this is just something thats been on my mind for a while. if i need to clarify further, pls lmk and ill try to the best of my ability.