Well, I'm pretty sure that they can do it techinically.
There are a good chunk of problems though, like how the Wii U's architecture is a mess, and how it would take a while to rewrite the game for the Wii U, and it'd be so much time and effort for a console that most third party devs don't even bother supporting as a result.
"Just for comparison Uncharted 4 was 20x bigger than Splatoon 2. This shows the huge difference between Sony's first-party games and Nintendo's first-party games."







