I doubt Nintendo will put Denuvo in any of their games, they've always been very mindful of their games being playable even without an internet-connected Switch.
What does that have to do with Nintendo using it in their games? That's Irdeto who decided to offer their DRM for Switch developers. As far as I can tell Nintendo is not involved in it, beyond presumably giving their OK.
Because the person you replied to gave a good reason why Nintendo wouldn't want to implement it, and your link didn't have any information that would refute that.
“Specifically, the first tool it rolled out is Nintendo Switch Emulator Protection, which protects games launching on Nintendo's hybrid console from piracy.”