I think it is more of what we grow up using honestly.

Even on mmos like WoW I can navigate and do things much faster on keyboard only, rift I had a hell of a time in beta because I was not use to using wasd at all.

For me controller with FFXIV feels the most natural, keyboard only feels the most usable (I can use macros and actions much faster), when I touch the mouse I just fail at everything honestly.