I believe I talked about this a long time ago, but with the Switch kicking @$& for more than 3 years now and still has some more years to go (if Nintendo permits), it’s kinda nice to see the narrative turn around a bit.
It’ll be a long while before Nintendo even starts to consider going third party. Sega had to because it was bleeding money by the time the Dreamcast came out. After the failures of the Sega 32X, Sega CD, and Saturn, Sega was in deep trouble when they released the Dream cast. Nintendo has had some failures, but was able to minimize the damages. The GameCube (despite selling ~21 million) was apparently able to sell at a profit thanks to its software. Plus the handheld division has been able to hold its own since the Game Boy, even if the 3DS showed signs of a decline in the handheld market thanks to mobile.
Not to mention that Nintendo, for better or worse, plays by their own rules. If they were to go third party, I would believe they would want adequate amount of control (and royalties) before they would even consider releasing games on non-Nintendo platforms besides mobile. They would want creative control, financial control, and messaging. You want high end graphical games from Nintendo? That’s not their focus. They focus on gameplay first before all else. Not saying other devs don’t, but you can tell the difference between their games compared to others. If ray tracing can provide unique gameplay opportunities, then Nintendo will look into if the pricing is right for their development.
Then again, you probably wouldn’t see much of their experimental works if they went third party. Nintendo is a toy company at heart so their devs like to experiment and implement new gameplay ideas, hence we have Splatoon, ARMS, Labo, Ring Fit, 1-2 Switch, etc. That’s just how they are. I personally wouldn’t have it any other way.