You cite Nintendo Land, except that it was a game designed to be the Wii Sports of Wii U.
That's exactly why I grouped it with NSMBU and contrasted it with stuff like Batman; Nintendo Land was a game designed to appeal to the Wii/DS/mobile-market. I understand this.
I'm looking at it in the sense that a lot of elements of the Wii U were designed to appeal to casual gaming (such as the whole idea of not being able to use the TV, which is more prevalent in Japan than the US).
Do you deny the fact that WiiU pad is basically a giant traditional controller with 15 or so inputs? Do you deny the fact that the Nintendo of 2011-2012 was making a big deal out of the fact that their relatively expensive new console could run traditionally young male-aimed software like Batman and Zombie U? Do you deny the fact that they were heavily promoting PS3/360-style games like Batman and Zombie U alongside youth/family/casual-aimed games like Nintendo Land?
Like I agree with you (and anybody else who's saying the same thing), it's quite clear that the WiiU focused on the youth/family/casual demographic in some capacity.
However, I also think it's incredibly clear (going by how the Wii U completely contrasts with the Wii in a number of important areas) that there was also a pretty heavy focus on trying to capture the young male/360/PS3.
I feel that it is undeniable that they were trying to kill two birds with a heavy ass stone and ended up knocking themselves unconscious.
My point of contention with your post is that you seem to imply that focusing on the Wii /DS/mobile audience again will be a bad because it's what has led to the failure of the WiiU ...yet when you look at the success of things like Animal Crossing New Leaf, Tomodachi Life, the NES, the Wii, the DS, every handheld that isn't the 3DS, the 3DS's bounce-back (with titles like Mario Kart and Super Mario 3D Land), and even the surprising success of the colorful/cartoony/simple non-violent Splatoon it's quite clear that Nintendo is usually at it's most successful when they focus on that audience (or an audience that's similar to it).
Honestly at this point, it seems like splitting their focus or going completely for the young male/PS4-audience with the 9th gen machine is just asking for failure (especially if they're not willing to completely change their branding, marketing, software focus/ecosystem, and general 3rd party relations)
Especially when you consider that all 3 of their failed home machines (in addition to problems like tyrannical alienating 3rd party relations, expensive cartridges, limited mini-disc, purple purse aesthetics, no online, etc.) focused on selling themselves to young males in some capacity.