I have one question: If Wii U is powerful enough to get all these "nerfed" ports from PS4/720 games... why the fuck is NSMB U running in 720p? If the Wii U can't even run that simple ass game in 1080p, I'm afraid to think of how the next gen games will run on the thing.
I remember hearing a response to that and they said it was developer choice.
My theories to why they would have made that choice are:
1. It's a 2D Mario game, it's not a graphic intensive game so 1080P would not even look that much different from 720P. It's not like Mario has or needs individual eye lashes or wrinkles under his eyes that we need 1080P to see.
Which kinda leads into number 2:
2. Nintendo has a lot of 1st party IP's that they know we want them to deliver on this new system. Why spend extra time worrying about 720P vs 1080P on a simple 2D Mario game when it doesn't add much of anything. They know we are screaming and whining for Zelda, Metroid, etc. No need to spend so much extra time on NSMBU when it's a simple launch game aimed to get systems out the door by saying "We have Mario at launch".
I don't want to say it's because their lazy, but I'm sure they just wanted to get 2D Mario done so they can start working on the Next big project.
3. It's a launch game and even though it's first party, maybe they still started so early they were on early dev kits and it was just easier this way.
4. This game is suppose to be the showcase game for marketing that you can play the game both on the TV and on the gamepad by itself. Perhaps if they went with 1080P, it might showcase a bigger difference that the gamepad vs what's on the tv would project to the customer and then they would get negative feedback from the press saying things like "gamepad view is ugly compared to what's on the tv". Keep the TV screen closer to what's on the gamepad like they did and we have already seen the press saying the Gamepad screen looks great.
5. It's a launch game, they are still getting use to the tech.
There's probably a thousand reason why they didn't go 1080P, that doesn't mean they couldn't.