Just because it works alright with a controller doesn't mean that the game wouldn't benefit from a complete MKB focus. That's quite an ignorant standpoint. Take Titanfall for example, supposedly a lightning fast FPS but in reality it's barely faster than CoD because It still needs to adhere to the same LT-RT control scheme. Dirty Bomb is a great example that would be impossible to play with a controller. The game is designed around super fast movement speed, no hipfire penalty and headshot multipliers.
I guess what you've seen / played of Titanfall was pretty low level to say it's no faster than CoD.
Wolfenstein and Brutal Doom are both fast paced, no hipfire penalty and headshots kill quicker and yet I had no problems with either on controller.
Still prefer playing my FPS games with a KB/M but this controller bashing shit is tiring. The games are all perfectly playable and beatable with a controller.