Wii-U sounds like an add-on to the original system, part of the reason why didn't take off is consumer confusion. The Wii-2, while still kind of dumb(because let's be honest, the Wii is a goofy name, although memorable), at least implies something new, most people immediately get the idea of it being a follow up to the previous system. And I don't think the Wii 2 sounds worse, because Wii-U, is indeed a dumb name, but that's subjective.
The Wii-U failed for a multitude of reasons that Nintendo got a salty runback with the Switch. It handled taking it on the go better(it didn't have limited range), more games that people could get invested in, Zelda being a launch title and Mario Odyssey being a true follow up to the Open World style did a LOT for them. A lot more third party support are all things the Wii-U lacked. The Wii-U price never really lowered either.
Also, just because people are memeing on it doesn't mean it's going to immediately fail. That's just foolish to believe. People roasted the dumb names of the 3DS' various off-shoots and upgrades, and last I checked, those sold pretty damn well, because, outside of the lackluster first year, the 3DS brought out games people cared about. And it's not the responsibility of the consumer to make a console succeed. It's the people making it, and a name alone won't completely doom something. Prices and games will help a lot.