If I were running AA, I wouldn't be threatened by all these mergers, either. This ain't the 80s, when mergers occurred to grow the network into new regions. Where does AA not go? Only the trans-Pacific routes come to mind. Between DL and UA (and to a lesser extent CO), the Pacific is sewn up. There's nobody to acquire there, and no more mergers that will be threatening there either.
Merging to reduce capacity is a fine thing for the legacy airlines as a group, but I'd want to be the airline not merging. Why? Mergers are messy and expensive to implement, especially on the scale we're seeing now. If the goal of merging is to swallow some other airline and quietly dismantle it, why not let someone else take on the expense? I'd get the same benefits (capacity reduction) for free.
Yeah, if I were at AA I'd love to watch the dismantling of US and/or CO by UA. Especially if it's CO. UA and US continue to struggle, but CO's mighty profitable for a legacy carrier. One fewer of those would do AA a world of good.