Look at the number of Pokemon Go players dropping really fast though.
This market you're talking about it extremely volatile, maybe they'll sell a lot of Switch during the first few months because of excitement/hype/word of mouth, but without third party support it will be left to die because most of these people won't buy the first party Nintendo games, just like they did for the Wii.
I feel like you're looking at everything around what it is and not actually straight at it.
It's a machine that plays home console quality games, but can also play them on the go. People are mindblown at the prospect of playing Skyrim or any massive recent-gen game at any place, at any time. There's no forced gameplay gimmick, as everything is controlled with the same buttons, sticks, bumpers and triggers. There is a unified, and overall traditional, setup to what this console is doing, and there's no strings attached. The visuals are wildly impressive for what it is, and nothing to shrug off on a TV either (unless if you're really that hard pressed all-or-nothing for top of the line 4K HDR 60fps gaming etc, but good luck finding people like that outside of Gaf).
Whatever strings people think are attached however are mostly due to telling themselves there is. Constantly repeating to one's self that it's a glass-half-empty situation ('an underpowered handheld with a tv output', for example) to act as if it's not doing anything to cater to it's home console audience, even though multiple things in the very trailer did just that.
The Wii U's biggest troubles was in a combination of
extremely poor marketing, splitting game development between itself and the 3DS (since quality / effort / budget on handheld titles were getting much higher) which led to less games, hilariously weak specs in comparison to it's competitors (where the gap between it and PS4/XB1 was so big that there was no way ports would work out well), and emphasizing it's gimmick to the point of requiring games to use it extensively over traditional controls (a turn off for everyone).
This, as we were able to figure out from one trailer alone, addresses and fixes each of these problems.
Nintendo for the longest time (since the NES) has been about taking video games the next step. The developers of the original consoles weren't gamers, because they weren't born into it. They created it. Nintendo continues to look out the box as they always have, taking it the next step and trying to look into other avenues that may actually help enhance and spread it out to newer audiences, while also keeping the old.
If you grew up thinking Nintendo's intention from the get-go was to put games on a box with a controller and that's it, then you probably missed that.
