Caveat - none of those - BotW, MK8, and Shovel Knight - are exclusive to the platform.
Also Splatoon 2 will be judged against Splatoon, itself an 80, so if it's not as iterative as it could be (i.e., more innovation than just halving the 2-map cycling from 4 hours to 2), it will review poorer than Splatoon. I see 78-84 for Splatoon 2.
Splatoon is 81 metacritic mainly because of the launch content
Splatoon 2:
- new SP campaign - judging from the Arms direct looks even more wild than the original
- New horde mode - Salmon Run.
- will launch with a lot of maps compared to the debut.
- maps will have a lot more elements from the SP(moving platforms, ink rails etc)
- easy to setup local multiplayer mode.
- Spectator Mode.
- Tournament Mode.
- all the existing weapons + new ones.
- new sub weapons.
- new specials
- new special moves(charges able to hold charge and jump with charge, dash for twinguns, faster movement speed for rollers, inking a path with rollers probably a lot of other moves/weapon mechanics we don't know about)
- new music
- reduced rotation 2 hours instead of 4
- can be played on a portable device or on the TV
- ProController support(no longer do you need to have the huge gamepad in your hands)
- Map is accessible via button rather than being marooned on another screen
- unlocks for clothes work differently
- PANTS and other accessories!
This are the changes just off the top of my head
It's a good game, that's it
I think you mean breath of the wild
Splatoon was #6 in GOTY overall list on this very site in 2015.
So obviously a lot of people liked it enough to vote for it over SMM, Undertale, Fallout and bunch of other games.
There is also the little matter of it being the most popular console game in Japan in the last decade or so.
It probably can't get a high meta like BotW, but in it will end up selling more and I can see it being top of a lot of GOTY lists for 2017