The continuity of Mario and Donkey Kong games should be taken as seriously as the continuity between episodes of ATHF or, if you want to use Miyamoto's own example, Popeye. Think of the characters as digital actors that can fill many story roles. Imagine Luigi of Arabia and Alec Guiness is replaced with Cranky.

Regardless of where Bananza technically lies on whatever timeline, they'll eventually release a game that doesn't agree with that timeline. I think this game implies that DKC happened long before Mario even had a mustache, like maybe around the time Yoshi's Island was happening? It won't stick. But I suppose it's amusing to consider.