I'd add Mario Kart 8 to Switch. While the game technically came out on Wii U first, it was a whole different beast on Switch. Not just the loads of extra content and features, but the portable mode of Switch takes Mario Kart to a whole different level. Being able to play multiplayer games at the office, while commuting, and capable of going up to 12-players, local; is a massive benefit over the Wii U version which is limited to split screen. Multiplayer has always been what makes Super Mario Kart great, and the game felt out of date on Wii U after Mario Kart 7 on 3DS took the multiplayer to the next level.

In effect, Mario Kart 8 was just another first party game on Wii U. The enhanced port was a killer app when it released on Switch.

So score that up for 2007, which (IMO) is Nintendo's best year of all time. In order to exceed it, you kinda have to be a bit hacky, like taking a 12 month span from most of 2007 from the Wii launch in 2006 so you can fit Wii Sports, Super Mario Galaxy, Twilight Princess, Resident Evil 4, Godfather, Scarface, Guitar Hero, Metroid, DS games from that stretch.

I voted 2017, but in hindsight I think I should have voted for 2022. 2017 had BotW and Mario Kart 8. But I really started playing Mario Kart 8 again in 2022, because of the DLC.

Anyway, they were both really good years, and 2019 was solid too.

Personally, 2021. Metroid Fusion, TWEWY and Pokémon Snap were incredibly important games to me, games that I came back time and time again over the years. So, recieving Metroid Dread, NEO: TWEWY and New Pokémon Snap, being able to experience these full on sequels and what's more, the fact that they came out SO GODDAMN WELL felt like a privilege.

Sure, in objective terms, 2022, 2023 and 2017 were absolute beasts. But 2021 was truly special to me.

Objectively 2023:

• Tears of the Kingdom and Mario Wonder-- two of the best games of the generation.
• Metroid Prime Remaster-- sets the bar for remasters with one of the greatest games ever.
• Super Mario RPG-- remake of an icon.
• Pikmin 4-- the biggest step forward the franchise has taken since it began.
• Fire Emblem Engage-- not much of a full entry in the series but more of a celebration of it; the worst Fire Emblem game is still better than the majority of SRPGS.
• Future Redeemed-- one of the best expansions of the generation for Nintendo's flagship RPG series.

Personally 2022: Xenoblade 3, Fire Emblem: Three Hopes, Bayonetta 3, Pokemon Legends Arceus, Mario + Rabbids Sparks of Hope and Triangle Strategy are all more in my wheelhouse. Also NieR: Automata, if I ever needed a portable version.

2019 for me as there was just an unreal variety of many of my favourite series.

It do be 2017 for me. BOTW and MK8D remain the 2 best Switch games ever imo. 
2019 was pretty solid as well.

For me, it's gotta be 2022.

2017, 2019, and 2023 were great too, but the sheer quantity of excellent software released in 2022 was unmatched in my opinion.
From first party stuff like Xenoblade, Splatoon, and Kirby, to third party efforts like Nier and It takes Two, I was practically snowed under with great stuff to play all year and well into 2023, to the point where I bought more games that year than any since 2010.

The fact 2017 is winning the poll by a wide margin is a testament to how incredible the combo of BOTW + Super Mario Odyssey was.

Nonetheless, 2022/2023 were indeed fire !!

This is a though one. Based on the games I spent mot time with 2019 and 2021 are high up.

2019 saw releases of Tetris 99 and Super Mario Maker 2 probably the two games I spent most hours with on my switch. Tetris simple pick up and play makes it a great game to waste a few minutes on when I do not want to commit for a long play session that I feel is needed to play other games.
Mario Maker 2 is for when I do have that extra gaming time. Like creating levels more than actually playing and tweaking the level to get just right is very enjoyable for me.

2021 got The Great Ace Attorney Chronicles and New Pokémon Snap. Both games that I never thought I would get to play. New Pokémon Snap was an absolute delight for fans of the original game, improving on almost everything that made the original fun to play and replay to get the absolute highest score. Did not think there was enough of an audience for a sequel but I am really glad it did.
Since they never localized the second Ace Attorney Investigations game I thought that the hope was lost to get the newest instalments in the series that was targeted at a Japanese audience. But behold! I have yet to play (or rather read?) through the game but my happiness of even being able to play it at all is enough for it to get a mention.

Based on other fan favorite releases I think 2021 have the edge over 2019. I still have a lot of 2021 switch gems to experience like Metroid Dread, Disco Elysium and Bowsers fury.

Two of the best games in a generation within a year....