Nintendo does not need equal 3rd party support as their competitors to beat them since they have much more superior 1st party and 2nd party support. Something around DS level 3rd party support would be good for them. Right now it feels like early Wii 3rd party support i.e 2007-2008. Indie games though make it feel much closer to DS levels though. Still not there yet though.
Most Nintendo systems have crappy sarts for 3rd parties. It will only get better though. Even the ok selling 3DS gained 3rd party support as time went on. The Switch is selling much better. I expect the third party support to start showing up this year and increase next year and again in 2021.