Shame on you OP for considering Zelda II a shame, it's one of the best ones there is.

Other than that, I would give 3DS to Mario and Switch to Zelda. It's already with just the games listed the clear winner imo. SNES would also go to Mario in my book. While I'm slowly warming up to ALttP, I originally hated the game because the knights were such pushovers compared to the ironknuckles I loved to duel in Zelda II.

But I think for Wii U, 3DS and Switch there's one thing you forgot: The Hyrule warriors titles. While it doesn't change the scoreboard for me, it may be the tiebreaker for you on the Switch.

I'd give the DS to Mario seeing as how NSMB was exactly as OP said - The revival of 2D Mario and it sold monstrous numbers - Best selling DS game after all. Whereas Phantom Hourglass and Spirit Tracks, while they have their fans, are generally a step down from prior 2D Zelda offerings up to that point.

As for Switch, I give that to Zelda. And I give it to Zelda just for Breath of the Wild alone.

Super Mario Odyssey is absolutely incredible, Super Mario Bros. Wonder is also a really great 2D platformer, and Bowser's Fury has me very eager to see what the next 3D Mario will be like - I'd love to see a full-fledged 3D game in that style!

But as outstanding as each of those games are, NONE of them were as crucial, as important, and as system-defining for the Switch as Breath of the Wild was. On top of being a fantastic game, one of the best ever (It's been voted the best game of all-time on this site for how many years now?), it was such a transformation and shift in development and philosophy for Zelda and Nintendo as a whole. It was EXACTLY the game the Switch NEEDED to take off. That late 2016-early 2017 period was a very anxious time for Nintendo. Their future was riding on the Switch's success and that sort of system and hybrid form factor had all kinds of question marks around it. Especially coming off the lukewarm 3DS sales and disastrous Wii U sales. It NEEDED that killer app to really sell the system to consumers and help it take off. It NEEDED Breath of the Wild.
Tears of the Kingdom is honestly the cherry on top of that.