So like I wrote, Switch will probably have best 3rd party support for Nintendo platform from SNES.
There are reasons why that's most likely scenario:
-Portability of Switch. We already seeing that people are buying same 3rd party games on Switch even they already have them on other platforms, and even if they are actually cheaper and look better on PS4/XB1, simple because full handheld mode is game changer for some people.
-Good sales of 3rd party games on Switch. This actually connected with previous point, but almost all 3rd parties until now that commented sales of their Switch games, said they are satisfied buy sales and promised stronger support. That goes for Indies and big 3rd parties.
-Great sales and popularity of Switch, that points that Switch will be very successful platform with big instal base. Obviously, much higher chances are that 3rd parties will support some platform if that platform is successful and has good instal base, because much higher chances are that they will sell more games on such platform compared to platform with low instal base thats not selling.
-Switch can handle downgraded ports of modern games. Regardless noticeable power difference compared to XB1/PS4, Switch tech/architect, tools, APIs...are very modern and Switch has support for all modern engines and APIs, so can handled downgreded XB1/PS4 ports. That's totally different compared to Wii regardless PS3/Xbox360 ports, and we already seeing modern games are ported to Switch.
-Switch is platform that's easy to work it. We heard plent of times (mostly from Indies) how Switch has great tools and how actually is very easy to work with, some Indies even said they ported their games to Switch in matter of days.
Evre past Nintendo platform after SNES missed some of points above, so thats why Switch will probably have best 3rd party support from SNES.
After Wii U fail, logically plenty of 3rd parties were reserved about Switch support, they went with "wait and see" approach, to see if Switch will sell, how popular will be and how fast can make some solid instal base, so plenty of them released only one game and some didn't release not single one, but after great sales and poularity of Switch in recent weeks we had plenty of annumcents of 3rd parties that support much stronger support in future, so we can expect much more 3rd party announcements in 2018. than we had in 2017. For instance Bethesda that wasn't making games for Nintendo platforms for several generations, already announced 3 (2 of them are alredy released) Switch games.
Just for record I dont think that Switch will have 3rd party support on pair with XB1/PS4 but can easily have best one after SNES for any Nintendo platform.