They'll make one for the NX. Wasting one on Wii U that'll maybe sell 600,000 copies simply isn't worth Nintendo giving a studio a big HD budget to make a Metroid adventure game with.
I'm sorry that Wii U owners want the sun, earth, moon, and stars for their console, but it's selling like crap. Many companies would've ditched it already. Be happy with what you're getting (which is honestly a pretty damn good fall lineup in Mario Maker, Xenoblade X, Star Fox Zero, Fatal Frame, and Mario Tennis) and stop complaining about what you're not getting.
There are limits to what Nintendo can do for a system that has this low of a userbase.
Also expect Wii U games greenlit later on like Animal Crossing Amiibo Party and Star Fox Zero to have lower budgets. Nintendo isn't going to break the bank with some super expensive HD games just so a very small userbase can (most of whom really will end up buying the next Nintendo console anyway when they see the next Mario/Zelda/Metroid/Splatoon/Mario Kart for it) be a little happier.
