Your right, 2D Metroid in design is completely different from the other platformers and I've played enough of the Metroid games to know that well. I was intentionally generalizing it as a joke just like many were generalizing DK. (literally any other studio could make DKC etc.)
Regardless, if Pachter is right about Wii U then I don't think there is any "What game can save the Wii U?". Mario Kart may help, but it won't save the system. Everything else might as well be a nonfactor (Smash, Zelda) considering that franchises like 2D Mario, 3D Mario, Wii Fit, Wii Sports, etc. were unable to turn the system around. As many perceived, Wii U is in a completely different boat from 3DS. The latter just needed a price slash and a good game library to get out of its slump, Wii U on the other hand seems like it is doomed to low sales simply because the market has no interest in the device.