I am not disagreeing with Dixie. But honestly its been so long since K Rool has been in a game that his impact has been lessened, and a lot of, and I know this is a sucky thing to say, "kids" or younger "gamers" (which is a dumb word to use but whatever) won't recognize him, though again, the more recent DKC antagonists aren't any more recognizable. Also not sure how well K Rool would fit thematically, but this game also has characters like Kirby and Peach so I guess thats a null point.

"Snake and Cloud are in Smash. 2 characters who have barely ANY history with Nintendo whatsoever got in before "

Smash is a celebration of gaming and those are two of the most important characters in the industry. Also, when you think of what Cloud means for Nintendo, he was symbolic of Nintendo's killing of any proper relations with third parties in the 90s. Cloud being in Smash, in a sense, represented, and still represents, Nintendo's recommitment to Square Enix, though that really happened like 15 years ago. Plus, Final Fantasy has a very long history on Nintendo, and Cloud is the most recognizable character in the game, so it makes sense to use him. Snake was just because Kojima wanted Sakurai to add him to Smash, and Kojima is Sakurai's buddy so he did it. He kills himself working on the game let him do stuff like that. And besides, if someone from Nintendo asked for K Rool, Sakurai would probably add him, so clearly no one at Nintendo internally, or Retro, is pushing for him either. Probably because he was Rare's character, and while Nintendo technically owns him, no one their has any creative attachment to him, which is for the better IMO. Forcing a character to be used by someone who didn't make them originally doesn't always end well in games.

"Sakurai could've EASILY added Dixie and K.Rool in Melee, Brawl, and Smash 4 but he didn't because I think he has a bias towards the franchise." Yeah... no...