I do think it will have to change the game, at least some what.
After all, more and more, what are these Japanese developers doing? They're trying to find a means to cater to the Western market. If MK successfully completes its mission to royally "spoil" the Western demographic, then it's going to change public opinion on just what kind of things that reviewers and lay people alike will accept and expect in a fighting game package. The dedicated fighting game buyer may not need anything more than a Training mode and a decent netcode solution, but that's not likely going to woo the casual buyer (who makes the majority of sales) any longer. They're going to want their extras and their fanservice.
So, I'm thinking that the likes of Capcom, ASW and Namco will be willing to at least pay heed to what may be the next big thing that helps woo people. And it wouldn't necessarily be the first time that MK may have been such an instigator. After all, the likes of Akuma, as well as so many other secret characters that appeared in other Japanese fighting games, largely came about because Reptile lead the way in how a secret character can only help drum up more support for a game.
The main thing is, if the game is good, the people will play. And even if you don't get the likes of Yipes and Justin Wong to "switch", there's nothing that says that MK can't craft its own scene, its own champions and etc.
UMK3 was able to sustain its own scene completely separate from the Capcom scene in the last 15 years. If push comes to shove, this new game can do that all over again, on possibly a larger scale.
