At the end of the day, no one bought X-2 because of the battle system or because it has boobs. It sold because it was the sequel of Final Fantasy X, that's it. X-2 is mostly an unnecessary and annoying game that it only serve to Square Enix gain more money out of our blind love for the franchise.
Yep. Those Square Enix dudes knows that you are stupid, and that you have money on your wallet and nostalgia in your brain. Deal with it.