NSMB is a 2.5D game because the controls lack depth, but it's more than that. If you took most of the models from those games, they don't have a back or side view. They don't need it, it's not modeled and thus any power that would be dedicated to that can go elsewhere.
While the camera is fixed in LttP2, the models are full and DO have backs and sides, and while the majority of the game is played on 2 dimensions, they aren't the SAME 2 dimensions. When you switch to "art" Link, you'd switching which 2D plane you're on. Those seperate planes make up a total 3D world.
I wouldn't be against calling the game 2.5D from a gameplay perspective, but from an artistic perspective it's fully 3D.
(edit) Also, for another page, this thread needs more video in action.
http://youtu.be/SE_xMCt9VLw 60FPS plays a lot into this because there are certain additional artistic limitations you have for the sake of better gameplay.