"We won't be working on WiiU because we are too lazy to put a map screen on the controller."
You can say this, but this is not new and is not localized exclusively around Nintendo.
1) Neo Geo was far more powerful than the systems of its generation. The result? Very few games were made for it because ports weren't easy.
2) The 3D0 suffered the same fate as the Neo Geo for the same reasons, despite having massive backing from some major third parties.
3) The Wii missed out on many ports not just because of its relatively weak power, but because of its unique controller.
4) Now the Wii U might lose some ports because of its unique controller as well.
5) Saturn is another example. Most portables don't get console ports. Many PC strategy games aren't made for consoles because the input method is so different. The list goes on.
This is simple math, really. If there are four systems on the market -- we'll call them A,B,C and D -- and A/B/C are all generally comparable and easy to work between such that I can easily treat them as a single, unified platform, while D is quite different in some major ways then D is going to lose out in most cases, even if D is very popular and well liked by many consumers. It doesn't really matter how it's different; history shows that if a platform is much more powerful, much less powerful, has a much different controller, or has much different architecture than its present day peers, it's going to struggle getting support.
It is unfortunate, but this is one of the primary reasons Microsoft and Sony tend to play it very safe with their hardware design; making something unique and different is very risky not just because you risk losing consumer interest, but because you risk losing developer interest, as well.