Nintendo's latest legal argument against emulators does rest on the DMCA's anti-circumvention provision. The letter from Nintendo to Valve in the Dolphin case makes it pretty clear.

> That's _not_ how it works and there are many court cases on point here.

Those court cases were overridden by Congress... when they passed the DMCA.

Under the DMCA, IT IS A CRIME to:

1) circumvent an "effective" copyright measure for any purpose, except specific, delineated purposes and cases which must be approved and reapproved by the Librarian of Congress every 3 years;

2) traffic in the means or technology to so circumvent a copy protection measure, with no exceptions.

The definition of "effective" is so weak that it applies to anything, even a bit of JavaScript that intercepts right click so you can't "Save Image As". It basically means, would the copy protection measure prevent copying "during the normal course of its operation". I.e., if it's buggy, employs weak crypto, or is otherwise trivially defeated, too bad. You can still catch federal time for breaking it.

In order for a Switch emulator to work properly, the copy protection on the game must be defeated. So even if you dump it yourself and a court somehow rules that copy to be fair use, YOU ARE STILL COMMITTING A CRIME by the very act of dumping it. Therefore, it is illegal to run a Switch emulator to play legitimate Switch games, irrespective of whether those games are "legal" copies or not. And a court may rule that Switch emulators are illegal to distribute as well, since they only have illegal uses.

I am not a lawyer, so I recommend you find yourself a good one if you want to mess around with Switch emulation. Best bet is to not get involved with it at all. Forget about preservation. The Switch and its games are not yours to preserve.

Well maybe, if you have the time and the money to make a fair use defense in court...

> You can't just say "SOME PEOPLE ARE USING THIS FOR PIRACY SO NOBODY SHOULD BE ALLOWED TO USE THIS LEGALLY"

That is in fact how many court cases are resolved.

>The legal uses as well as the plausible fair uses need to be evaluated before you can say "nope, this has gotta go".

what "fair uses" do we really have to stand on? "I can play Nintendo games better on my PC"? Are you a university or organization trying to preserve software?

At the end of the day, video games as a whole are not a societal need. So it becomes hard to make some argument against having IP owners not clamp down on entertainment intended to make money.