I think the Splatoon franchise’s greatest innovation is explicitly establishing that Inklings are dumb as hell, because that way they don’t have to do any backflips to justify the plot. Everyone involved canonically has the mental acuity of a bowl of porridge, so just go with it!
*emerges from the depths of hell, one of few octolings to ever make it out alive*
HEY DO YOU LIKE PULP IN YOUR ORANGE JUICE??? DO YOU LIKE FUCKING PULP IN YOUR JUICE YOU WEIRD LOOKING SQUID???? WHO DID YOUR HAIR
Not that Octolings are much better. To put it in D&D terms, where Inklings dump-stat Intelligence, Octolings dump-stat Wisdom: technical brilliance paired with all the common sense of a sponge. We are talking about a people who lost a war because it never occurred to them to buy longer extension cords.
The salmonoids have developed advanced technology and are the only race capable of surviving in the oceans, but their lack of tactical skill and the deliciousness of their eggs causes them to regularly be slaughtered by inkling children taking a break from the turf wars.
conclusion, if someone can get a single inkling, salmon and octo to work together, they can rule the world