Nintendo wants 3rd parties, but they want money and continued survival most of all.
Due to the fact that Nintendo is just a Japanese card company that wandered into toys and only struck gold when becoming a video game company, its reserves and cash flow is dwarfed by that Sony which exploded thanks to worldwide electronics brand or Microsoft thanks to its OS core technology brands. Nintendo can't enter a straight shooting war with Sony and Microsoft and win, the few times they tried to match or exceed them were the N64 and GC systems with the N64 being the only one to place second of those two systems. This is no doubt a problem especially in the current generation which seems to have had more Western PC developers leading the pack of third party gems.
Yet, there is a strong sense that even had Nintendo created a system on par with the PS4 (which we don't know if that is or isn't the case yet) there is a possibility developers will still come up with excuses as to not port their games. Nintendo has seen this throughout the years, certain 3rd parties both in the West and in Japan rather then releasing games that could be easily ported to the GC, Wii, Wii U and even some 3DS games would choose to just release it on competition systems. Also one merely has to look at Xbox and its own struggles, sometimes even if you have a comparable system a decent set of exclusives, it doesn't mean you will be able to take a strong standing with certain factors such as one company getting a strong early lead and preference among developers. One would literally need a handheld Monster Hunter style money maker to pull a system back from the brink such as the PSP saw in Japan.







