It's November 21st 2016. The NX is out and more powerful than the PS4. Are 3rd parties on board?

[Miyamotoo]

People forgetting that 3rd party were even on board on Wii U at launch, but they all abandoned Wii U in first year after terrible sales.
If NX actual sale and have similar PS4/X1 architecture and power that lead to easy ports, they will probably stay this time.