Sometimes it is good to have a mode for when you can't get together with friends. (Also, I think Splatoon needs a single player campaign, which it has done a great job with for both games, as the game will become obsolete when online is taken down. )
My problem isn't that there should be a great story in Smash... It is just a bit of a disappointment when you lead with something like the opening cutscene in the World of Light only to find out that there is essentially nothing to come after that.
Yeah, I agree. Splatoon does have a single player mode but it´s not long. The Octo Expansion adds a lot to the single player experience of Splatoon 2, though.
That game, at least, is playable locally. Given, of course, you can gather at least 04 players each one with its own Switch.