QFT. If AA gets buffed to the point where they can reliably kill any aircraft they see, then air will not be viable at all. Unlike ground, you are completely exposed in the air. AA MAXs are already effective right now in driving off air right now, they simply don't get rewarded for it, so people don't like doing it. When a couple AA MAXs do get together, it's a very effective defense in it's current state.