I don't know. Sure, a few games/developers profit from it but what typically passes as a commercial game
isn't of much use in training and education. Outside of this rather narrow field of T&E suitable programs the involvement of armies doesn't play a large role, for better or for worse.
Maybe armies could select from a broader range of products if they subsidized game developers on a broader scale but let's be honest, it wouldn't be politically palatable if tax dollars were seemingly wasted on rather unspecific "game development" in the hope that out of five or ten games on which money is spent, one useful product will eventually emerge.
IOW, the market is about as impoverished as it gets.