The real problem is AAA studios not putting the huge money behind a game. At any given point, there's 9 studios working on COD (there may be even more).
With the recent BF games, it is clear they don't have the $$$ behind them like COD. I mean, BF V could have been much bigger, but the content was still far too little, far too late. Even their BR game had a ton of potential, but never got any development, so it felt half baked at best.
Just googling, it claims that BF V cost $3 mil to make, while MW2 cost $250. I don't think it is any mystery why BF isn't pushing COD.