alt Hacker NewsNintendo obviously doesn't think they have standing against emulators [0]. However they they can make the lives of defendants hell until the emulator devs settle.
Now, I think there are laws to curb this kind of judicial abuse, called anti-SLAPP laws. But reading about it, it seems to apply to defamation lawsuits. Apparently it's okay to threaten legal action in bad faith when it's, say, regarding non-existent copyright infringement.
https://en.wikipedia.org/wiki/Strategic_lawsuit_against_publ...
[0] to be fair, they might get something out of the anti-circumvention clause of DMCA. But this only applies if devs aren't careful enough (or don't know about this technicality). Developing an emulator to run legally acquired games doesn't break any laws.
>to be fair, they might get something out of the anti-circumvention clause of DMCA
Nintendo's entire case rests on DMCA 1201. It entirely circumvents (pun intended) the reverse-engineering case law[0] most emulation developers point to. In other words, they aren't saying "you can't write a Switch emulator", they're saying "you can't tell people how to rip Switch games".
The problem is that a DMCA 1201 compliant Switch emulator would be nearly useless. To be clear, the legal way to use the emulator on your own purchased games would be entirely undocumented. You probably couldn't even say "figure out how to rip the games yourself". The illegal way to use the emulator - i.e. with pre-decrypted, pirated game files that don't rely on any Nintendo keys - would be very easy. But they can't tell you to do that, that would be inducement.
Homebrew developers could still legally release their own games for use in a Switch emulator. And emulator developers could advertise the use of the emulator with those games. But that's really limited and I could see Nintendo convincing a court to just ignore it.
[0] e.g. Sony v. Connectix