I guess they want you to use the smartphone app in speaker mode? It makes a lot more sense than that wired mess they showed when Splatoon 2 got voice chat.
While they can’t control 3rd party games, Nintendo seemed confident they could charge you for buying Virtual Console games on a per-system basis. Super Mario World on the Wii, WiiU, and New 3DS required 3 purchases even though I have to log in with the same Nintendo ID. And if I wanted to play it on 2 Wii consoles I had to buy it twice. I think adding the online features and switching to a subscription based service was their way to avoid asking people to buy NES games again without giving you access to stuff you already bought.
I’m still waiting for GameCube games so I can Fire Emblem without paying $200 for the disc.