You're probably right, but there's at least one emulator out there that can run relatively modern games at a comparable speed on unsupported operating systems:

You're probably right, but there's at least one emulator out there that can run relatively modern games at a comparable speed on unsupported operating systems: WINE (and subsequently Proton and Crossover). [1] While I don't think APIs are generally copyrightable (IANAL) so WINE should be in the clear, I could totally see a universe where Microsoft decides that WINE is a threat, and they bully them through the legal system to stop development. Will this happen? Probably not, but it's just one example that could happen. Hell, Crossover even monetizes it, which is part of the issue that Nintendo had with Yuzu isn't it? [1] Yes yes I know "Wine is Not an Emulator", it's a compatibility layer, but it still more or less functions the same way as one for the sake of this argument.