That's the issue. They were the exact same games (performance issues on older hardware excepted). Here are two reasons to justify this.
1. Having WiiU or Switch games features watered down to match what the 3DS can do is not a good thing. This removes features from the TV version of the...
Why is the Switch better?
Better SDK than the WiiU had
Nintendo is really doing everything now it can to court the 3rd parties
Ease to port games to Switch has been mentioned a lot, a lot easier than in the Switch
Tablet like portability
Good motion controls, unlike the Wiimote
Nintendo...