It already was, in my opinion.
By having removed the original creator and the semblance of an overarching story, they have effectively lost any conductive thread the series had. Its only the same game over and over in a different setting. Black flag spurted the downfall a bit because it looked to be different (more of a pirate game than assassins creed), but i am expecting the series to dramatically decline with this release.
This is what happens when you milk the cow too much. Call of Duty will eventually follow suit.







