Emulation was getting to be a pretty big problem by the end of the Switch's life. People would get a hold of a game, dump it, and get it running in emulators prior to the game's release date. IIRC Super Mario Bros Wonder leaked around a week early, and Zelda Tears of the Kingdom leaked around two weeks early. Obviously you can't quantify how much of an impact this had on game sales because time travel doesn't exist, but I imagine that there's some impact on sales when a highly anticipated game is playable for free prior to its launch date.

Besides the issue of games leaking early, piracy groups would also use Switch emulation as a workaround for the PC version of a multiplatform game having Denuvo DRM. They would make an installer that bundled the Switch version of a game with a preconfigured emulator, so people could run the game by double-clicking an icon without having any knowledge of how to set up a Switch emulator. This isn't really relevant anymore because of hypervisor cracks making it far easier to bypass Denuvo, but I think it demonstrates how widespread Switch piracy was.

I agree that this won't have any sort of major impact on Nintendo's bottom line, but I imagine it'll have some impact. I doubt this will lead Nintendo to change their exclusivity policies. They didn't change anything when the GBA was emulated during its commercial life, when DS piracy was rampant during its commercial life, when Wii piracy was rampant during its commercial life, when 3DS piracy was rampant during its commercial life, or when the Switch was emulated during its commercial life.