No, I don't think that status is detrimental... and that's a bit hypocritical, I admit. But I have three differences that make the cases distinct enough.
1) It's first party. This to me will stick as a very thick line.
2) The fact that Splatoon is, and has been since launch, a massive success of a title on the worldwide scale exceeding Nintendo's projections (physically having less copies than demanded by the public).
3) It's spread so far across the actual game, the OST selling great, and the actual official manga being supported that I don't see it NOT being continued. The last time we saw a Nintendo IP go multi-media and have this level of infectious success was... well...
![Pikachu :4pikachu: :4pikachu:](data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7)
.
Yes, it currently is just a game. Yes, there's no PROOF that it will be a series (The title Spla2ne still needs to be a thing). However, it's a first party home run of a title that is the entire market with Nintendo and the genre (unless you want to stretch and include
![Samus :4samus: :4samus:](data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7)
). They're two separate beasts to me.