This is true, but the slight difference is that the WiiU extremely undersold. A significant number of people who own a Switch did not own a WiiU-- I myself did own a WiiU, and was bummed to not be able to play Mario Maker, Splatoon, Mario Kart 8, 3D World, and so on... but most of my complaints were met with re-releases and sequels. I can't say I entirely disagree with the decision, again since the WiiU was a major flop, but it would have been nice to have my WiiU library brought over. But for most people, they didn't care. I mean, MK8D sold more copies than the WiiU itself.

But this is a different ball game. The Switch is a success. Many people own a Switch. The Legend of Zelda games on Switch are among the highest rated video games in history. If this catalog is lost when transferring to the next console, Nintendo would absolutely be shooting themselves in the foot. Historically, Nintendo is somewhat on board with backwards compatibility, but not always, so we'll see.