I don't know. Usually I agree with your takes, but treating the Switch like a $300 controller to enable the gimmick that failed to gain any interest for the Wii U? It makes no sense... which, come to think of it, is the only reason I'd believe Nintendo planned to do it.
What would be nice, wireless connections-wise, would be the ability to stream to another screened smart device (be it Switch 1, Switch 2, a smartphone, or a tablet) for local multiplayer on the go. And if it just so happens to also do the Wii U thing, that might be worth the time to program.
No matter which way you frame it though, the basic idea doesn't seem like a gimmick worth the time to figure out. Maybe a demo will sell me on the concept (assuming it's true). *shrug*