I've been saying for years that DK fans are too polite and just assume Nintendo will cater to their every last desire if we wait another 5/10/15 years. It's almost like we've completely forgotten the amount of bitching and campaigning we had to do 9 years ago just to get K. Rool into Smash. The bitching of Metroid, Zelda, Paper Mario and Smash fans is what gets them such good treatment (I say this as a Metorid, Zelda, Paper Mario and Smash fan).
Not advocating for death threats or any of that garbage, but DK fans DO need to bitch more if we want Nintendo to give us more transparency about the series and let them know we want classic kongs and kremlings to be in newer games. Even if you know there is a new game coming and it will be a masterclass platformer, ask for more. Doesn't sound nice but it is what works