A Nintendo only console (basically) on top of being expensive would be a instant bomba.
To be honest I don't think NX is going to work any miracles. If unified it'll probably sell a decent 60-65 million or so, the vast majority of those being the handheld variant. It'll make Nintendo a decent profit, but they're not going to be a big time player in the home console world. Not unless Sony makes the PS5 $700 or something, which I doubt.