the PS2 was competitive. It doesnt mean at has to be on par or ahead it just cant be a whole gen behind. 

Where are you getting this idea from? Nintendo actions and words have only shown the opposite to be true.

Then explain 3DS vs. Vita.

First: Everyone needs to stop taking those current rumors for the holy truth. Seriously, guys, just remember what happened last time everyone thought that the rumors just HAD to be true:

yup.

Thats what I'm talking about!

To get back to topic:
Nintendo doesnt need the most powerful system or even something close to NEO or Scorpio to get solid third party support. They should try to get on the powerlevel of Xbox One and PS4, but even if they dont (which I doubt, there isnt that much room between the Wii U and the XOne to begin with)
they could still get Third party IF they make the deals personally and/or the console sells very well.
I'm pretty sure that, if the Wii U had sold well, many third party games would have gotten Wii U versions. Scaling things down is always possible, its just very time-consuming and annoying, with a lot of trial an error, so you wouldnt want to do it without a solid reason.

At the end of the day, I am afraid we must not forget that Nintendo hasnt been big in the third party game for quite some time now, so getting back in there will probably take a bit longer then most here hope.

Again, I do agree that a stronger system could help a lot with this problem, but its not the end-all-be-all!
A weaker but cheaper system with the usual Nintendo Quality but without the Wii Us droughts could do wonders, and maybe pull some third partys back in. Then we can look further, step by step, one after the other.

And the NX won't be a whole gen behind. Its graphics are stated to be somewhere between PS3 and PS4's. That's roughly what the PS2 was in comparison to the GC and X-Box.

@OP. You certainly know how to attract attention. You might be the Ted Williams of VGChartz with that post-to-points ratio. I partially agree with you. I mean, of course third party support would be buoyed if spec parity were a reality. And I don't really see a downside to the "more power and more support/games" scenario.

First of all, if the rumours about NX are true, it's cutting edge, not outdated.

Secondly, third party support doesn't mean the same thing today as it meant even just 5 years ago. Indie games have taken the industry by storm, and AA titles are making a bit of a comeback as well. Mega publishers are starting to release some small scale titles, and the big blockbusters are taking longer and longer to complete.

NX can still have large library of quality 3rd party titles without having super powerful hardware. What they need to do most is to improve 3rd party relations and make an approachable platform.

Why would somebody need one console that plays the least amount of games?

According to Nintendo's quarterly earnings, 3DS+Wii U have about 600 retail titles, when including digital titles that number is over 1000.

Keep in mind that if the rumors are true, NX is a successor to both 3DS & Wii U so if it can retain most of the support that those 2 devices had than thats a platform with over 1000 games.

Stating opinion as fact, that's a true failure.

The best answer is because it plays games you can't play anywhere else.

Chance-the occurrence and development of events in the absence of any obvious design.

Wii certainly didnt succeed by chance, Iwata and Co. had a clear vision of what they wanted Wii to do and who they wanted to sell it to that is the exact opposite of chance. They had a strategy and strong execution.

There is no real reason why NX needs to be as powerful as Neo/Scorpio, that would be suicide as it would be the most expensive Nintendo console ever and if you think Nintendo took a long time to get software out on Wii U than just wait for the device that is 20x more powerful.