What's the definition of 'evergreen' now?
As far as first party Nintendo software is concerned at least.
I don't know if would personally consider TOTK at almost a year old an evergreen title, as such, but I understand the industry can and probably does… if that makes sense.
I once got confused at some reporting that labelled a game this when it was only released six months prior, and wondered ever since. I think it was something like Splatoon.
I don't think TotK is an evergreen yet. Obviously BotW is but it proved that over years. Zelda is new to the evergreen thing unlike say Mario 2D where I'd automatically assume that Wonder is an evergreen now in place of NSMBUD.
I think we really need to see multiple years of >1 million FY sellers for a title to label it an evergreen. That's the definition to me: "does a title keep showing up in the list of FY 1 million sellers, 2+ years after release?" TotK likely will achieve that with an upscaled Switch 2 release (perhaps with a DLC added).
If you look at the current list of evergreens on Switch, it's basically: Kart, Smash, Mario 2D/3D mainline, Mario Party (both), Animal Crossing, BotW, Super Mario 3D World+Bowser's Fury, Luigi's Mansion 3, and Ring Fit Adventure.
Titles that are likely to be evergreen over the next ~3 years: TotK, Nintendo Switch Sports
I would exclude Pokemon because they are quite JRPG-like in terms of having explosive initial sales with smaller tails. Splatoon hasn't quite proven to be evergreen yet either.