I think people saying "well the specs aren't high enough so it should be cheaper" are missing the real issue.
If you don't have an Xbox One, PS4, or Switch, and all three are the same price (and all three have pay online, and the Switch has the most expensive extra controllers but also sort of a second controller packed in), but the Xbox One and PS4 have 4 years worth of excellent games available for cheap and all the hottest new releases, while the Switch has Nintendo games and a handful of versions of third party games, most of which will almost by definition have smaller communities or technical limitations or both, then the Switch is going to seem like a worse value for a lot of people. It's true, Nintendo games count for a lot. That's why there are 12 million Wii Us sold and not 0.
If you do have an Xbox One or PS4, maybe you would consider the Switch as a second console. You'll buy most of your stuff on your primary console, but you'll check out Nintendo games. But the $300 upfront barrier, plus online subscription if you want to play online, makes it a much bigger hurdle when you know you could get 4 or 5 new release games for your primary console for the same price.
But the other major risk is that the Switch launches at $300 and then within 6 months the Xbox One or PS4 get to $249 or $199 or they are $299 with aggressive bundles that have two or three games. Now all the problems I mentioned above are actually exacerbated.
Now, maybe you say that there's a target audience with families who love Nintendo games and don't want AAA shooters because their kids are too young or whatever. I buy that, for sure. Except that almost everything in the kid/family market segment has run for mobile and tablets, which the family already has, and among licensed movie games, they can get those on Wii U, and if they want to buy a dedicated system, it seems to me like it still wouldn't be obvious that they'd pick the Switch as that system even just for family-dedicated titles.
I think if the value proposition of the Switch is "well, it's like the Wii U, except we stopped making a dedicated handheld so now you need one of these to play the games you used to play on the 3DS", then it will do better than Wii U but a lot worse than Wii U and 3DS put together.
(Full disclosure: I'm trying to choose between GameCube tier and "above GameCube and Wii U" tier)