Also, to supplement the 3D vs. 2D on WiiU argument, Zelda is an advertisement vehicle.
Maybe that's Nintendo's biggest gain from the franchise. Even if it doesn't sell as much as Mario does, everyone looks at the Zelda games to see what a Nintendo console is about; it always shows off the system. It's always a proof of a system's capability. It's continuously been critically one the highest rated franchises out there. It makes the press turn their heads. People buy a system for such a game and they have to go all out with this game if they want to retain any credibility in the eyes of the press, the industry and the consumers.
Putting out an 'underwhelming' Zelda game, one that isn't in the realm of expectations or one that doesn't push a system to it's limits, would be bad press.
Now directly at the premise in the OP; I wouldn't mind the main mechanics of A Link Between Worlds to return for handheld titles, which is what I think Aonuma is alluding to here. For consoles though, they just can't for reasons above and I personally would want my console experience to be as grand as possible which top-down games just don't do (even when Link's Awakening is my #2).













