No one tell him
I think it's cute how Nintendo is fond of having you shoot through the air at high speed between different platforms, and inventing new ways to do it. In Galaxy it's the launch stars, in 3D World it's glass pipes, in Odyssey it's power cables, in Bananza it's monorail minecarts.
My only other opinion is that setting it fully underground and then making basically all the areas be floating islands beneath bright artificial skies feels, hmm, like a striking lack of faith in the whole concept.
I watched a longplay of Bananza to see what it's actually like, and by far the most entertaining part was the longplayer having the girl wear this freaking get-up for all the serious endgame cutscenes.
In Donkey Kong Bananza™, you'll be shocked by a surprise team-up between DK and the most unlikely of characters… none other than Muddy Mole from Mole Mania for the Game Boy! The two brown beasts combine their digging skills to mine the Golden Bananas and the Crystal Cabbages!