That's pretty far out of left field. The Switch is not really a dedicated portable or home console. It's a hybrid. We're entering new uncharted territory for Nintendo, where for the first time since 1989, they are NOT going to have a Home Console over here, and a Portable Console over there, separate. They are now going to be one and the same, there will no longer be two sets of games for each, there will no longer be a need to spend next to twice as much money on both systems, there is no longer a need to worry about connectivity between wildly disparate versions of games (like Smash). It will just be one unified unit, with (theoretically) ALL the games that used to come to GBA/DS/3DS and GC/Wii/Wii U (just for example), will release on one system now, at the very least giving it a better flow of FIRST party software.
How third party software pans out, as well as how Nintendo manages to market the thing (because their Wii U marketing was a disaster), remains to be seen. On PAPER, the Switch (while I don't love the name) concept sounds great. I have never been huge into portable gaming, mainly because I prefer to relax at home and see my games on a big screen. I also simply don't feel like playing games much when I AM on the go. But it would be great to be able to take the game I was playing at home, and keep playing it on the road, if I want. It would also be great to, for example, NOT miss out on some great software, because I own a Wii U, but not a 3DS, or vice versa.
So no, I would not say that Switch is the spiritual successor to anything, at this point. This is Nintendo attempting both a last ditch effort to regain the footing they lost with Wii U, and also them somewhat hitting the reset button on the entire way they've operated for decades, now having one "unified platform", instead of trying to prop up two separate systems all the time. On paper, in theory, the idea is that the system will play like their home consoles, but (Wii being a recent exception) will hopefully SELL more akin to their portable systems.
We shall all have to wait and see how that actually winds up playing out. I personally am still incredibly burnt by the whole Wii U experience, having owned one since launch. But I do WANT Nintendo to succeed, so I hope they've somehow learned their lesson and make all the right moves this time (even though their handling of NES Mini doesn't help my confidence in them).