Wii U's main graphical disadvantage is the lack of a studio like Naughty Dog or Santa Monica

[GameAnalyser]

I only blame the misplaced timing for launching their console in the market. Wii to be blamed partly. It was an under-powered console that succeeded so well that there wasn't a need for another console for a longer period. So when its sales began heading south in 2009 with PS3 and 360 competition, Nintendo had to somehow end the drought with Wii U. Nintendo should have waited some more to match with PS4 and Xbone  specs and thus apart from first party studios( the current life-line), graphical advantage would have been enjoyed along with a strong 3rd party support. Wii U is currently lacking this trend and it is turning out to land it in trouble as the Gamecube and N64 examples.