Those who are honestly dissapointed with power. Lets say Nintendo went as powerful as PS4 or slightly more. And is around the same price range. It will get more 3rd party support on the get go no doubt nit probably still not as much as PS4 due to smaller userbase. Do you honestly believe it will be a success. I think it would be worse than GameCube scenario atleast GameCube was extremely cheap. There is no room in the market for another platform that is similar to PC, XB1, PS4.
The best course if action is to be the budget secondary console and target current gen owners who want a cheap side system which plays Nintendo games and has some unique experiences. They should target to be a secondary console and a cheap system for kids and casuals. The advantage of this the power level would be close between handheld and console and they would be able to have a unified software output with no draughts which would make the system rather appealing. Imagine a cheap $250 console that plays every Nintendo game such as Pokemon and Mario. As well as those unique Japanese games. I'm sure western indies will be aboard as well and maybe even some bug western publishers may take notice later down the line if sales are good. Imagine COD4 remake ported to NX it would be cool to have a proper COD on the go.
I'd actually say the complete opposite of this is true, and if anything now is the perfect time for Nintendo to make a more traditional console and gain back a huge amount of ground their failed approach of cheap systems just for Nintendo games has cost them over the last decade plus.
Like it or not, the PS4 and rise in PC gaming shows us what the market is actually interested in.
Even the Xbox One fucked that up, and that leaves an opening for Nintendo, with its huge amount of brand awareness and nostalgia in the US, combined with far better standing and audience diversity in the rest of the world, that they could, with the right rebranding, third party deals and marketing, use to take second place this gen and be ready for a real fight once the PS5 and NX 2 set things back to 'zero'.
There's simply no other option. No matter how low the price goes, a Nintendo only console will sell less than the WiiU. Mobile will continue to sap the numbers from handhelds until it's into the niche numbers of dedicated cameras, sat navs and all the other tech smartphones killed.
There's a very healthy dedicated gaming and particularly console market that we know from previous gens can support 2 systems very healthily, and currently only has one player in it that didn't spectacularly fuck up, and there has never been a better time for Nintendo to right their ship and become that second player.
Just sticking the course and selling to the ever dwindling hardcore is just putting their fingers in their ears and shouting that what everyone wants is wrong while heading straight toward an iceberg though.