It's all guessing. My guess is that about half of those are lost sales. The kind of person who does this is obviously interested in the game. Emulating Switch 2 isn't a hacker task but isn't easy, so they were determined to play it. I think they'd buy it if there were no other choice. This emulation also requires a powerful PC, so they have money.
An opposite example would be emulating random NES games, probably only trying them out. And those are still sold on Nintendo's virtual consoles.
Just absolutely unfounded guessing here. You're literally just spitballing based on vibes and nothing else.
There's an easy way for Nintendo to shut down most piracy from people who just don't want to buy a switch 2 and pay an arm and a leg for the super-fast cutting edge microSD only compatible (at this time at least) with the switch 2 - just make the games available digitally on every platform. I don't want a bunch of locked-down consoles with different stores when I have fully owned-by-me PCs and handheld systems capable of playing everything already.