IIRC this is what is currently protected in American law, but the problem is that in the time between now and the Sony/Bleem lawsuit Congress passed the DMCA, which has a provision making it illegal to bypass copyright protection. When emulating any modern console, you are naturally required to bypass the copyright protection on the game, which Nintendo would argue makes it illegal to do.

Maybe you could get around this with some kind of emulation scheme that requires the console to be plugged into your PC, like the emulator uses the console's official hardware for the copyright check and then just takes over rendering the game.