In the end I feel the blame is on Nintendo. They set the direction and general tone for the system. They're the ones that launched the system without a clear message. That didn't listen to the concerns regarding the naming of the system. Didn't have the games ready in a timely fashion after having how many years to prepare having seen the troubles others went through!?
However I think a big issue is that Nintendo simply isn't cultivating a large enough audience that will play third party games. The action games, shooters, etc. Just look at their holiday offerings. Two platformers that slant either to the 2D or are outright 2D. That might sell hardware but it's going to be to people that then turn around and buy the next Call of Duty. Or show Activision that there might be a market in large enough numbers for a Wii U version of Destiny.
Iwata can say all he wants that they are working to build momentum for the Wii U. However the announcement of Donkey Kong Country Returns: Tropical Freeze sends a very specific message and it's not a message that is going to be attractive to third parties when they look at what type of audience Nintendo is trying to build. This is on Nintendo because they don't put out their smaller brand titles anymore. Where is Wave Race and F-Zero? Where is 1080? Why was the Excite series and Battalion Wars series handled the way they were? Whey did they not follow up with another Metroid Prime when it was clear FPS were going to be the genre of the generation after Metroid Prime 3? Where is Star Fox?
These are the game series they have that could have helped cultivate an audience that would have been open to buying third party titles in larger numbers. They did either nothing with them since the GameCube or they just tossed them out there on the Wii in such a way you have to question why they even bothered. I'm sure third parties are seeing this as well. They might not have brought in the money Wii Fit would have but you have to keep your customer base happy and maintained as to not make them ripe for the picking by other companies. I don't think they ever gave any thought to this. Unless they felt it wasn't needed and they really thought all the people they sold to would stick with them so they could afford to toss aside long time customers.
This is why I can't take what Iwata is saying seriously. Why I don't think things will change around for the better with the Wii U when it comes to games I want to play and experiences I want to have.