There really aren't any big Nintendo villains like




, are there?
The more minor villains like



are great and fantastic additions (calling Jr. a minor villain feels odd).
And the anti heroes




are amazing as well.
But there aren't any more big notable main villains left, are there? A lot of smaller franchises have recurring villains but they aren't huge big deals like Bowser, Ganon, Ridley or K. Rool. There is a certain lack of star power there. The only missing villain that I think has equal star power to the above four is Giovanni. And I don't think he really works as a playable character. A lot of his would be menace was given to

anyways.
It seems painfully obvious why they chose to include

now (and technically

). Nintendo ran out of major headlining villains. They need other companies to keep including them.
I think DJ Octavio is the only Nintendo villain who could eventually step into that kind of role. He's reoccurring. He seems to be an ever present part of Splatoon. Splatoon is major enough that he may become large enough to make it work.
There's Kamek, I guess, but he's playing third fiddle to both Bowser AND Jr. Nintendo likes to play with the Bowser and Jr. bond, but they rarely have the trio interact as a villainous triumvirate.