I mostly agree, but I'm worried about what it means for third-party support.
If the Switch is significantly underpowered compared to the competition, it means that developers won't be able to easily port XBone/PS4 games to the Switch which will hurt the Switch's lineup. In that case, Nintendo's best hope for success is that their Blue Ocean Strategy will take off and people will treat the Switch as not just another console but as a supremely versatile handheld.
The reason the Wii got away with it was a) Blue Ocean Strategy gave it genuinely unique games and b) the PS2 was still kicking around so the Wii version can easily be ported to PS2 and sell on twice the number of consoles (i.e. they'd make a 360/PS3 version and a Wii/PS2 version).
The Wii U had beautiful games with beautiful art direction (Yoshi's Woolly World, anyone?), but it still flopped largely because third parties ignored it and Nintendo didn't have a good enough Blue Ocean Strategy.
With that combination, you need something like the art direction of a Studio Ghibli in order to successfully manage the complexity (excited for the new Ni no Kuni, BTW). Most, maybe all, game studios in the west are not up to the challenge. Many indie games are much more artistically successful precisely because they have to think around the constraints and can work with a more concentrated vision.
Hyper Light Drifter is one of the most beautiful games I played to.
For me the Switch looks powerful enough to run beautiful games. A good art direction trumps raw power in almost all cases.