I have read comments from game developers that copy protection, and anti-piracy tech, does seem to have a significant and positive effect on a game's sales for the first few days after release, which seems to be a hugely important window in a market with a short attention span and a constant flood of new games.

I agree that the big deal that Nintendo must be worried about is Switch emulation and piracy/leaks of new games before or close to release.

On the other hand (refuting my GP speculation perhaps), are Switch (and Switch game) sales really going to tank because pirates can run Zelda on Steam Decks? Regular Zelda fans who can afford one probably own a Switch already, are planning on buying a Switch 2 (or an OLED Switch after a price drop), and preordered the game.