When I said "should be", my primary concern isn't necessarily the well-being of Squaresoft. Mickey Mouse becomes public domain in a few years, if I remember correctly. Disney will lose millions of dollars. Eventually, things pass from the realm of money-making to the realm of being part of our culture. In any case, no one is making money off of selling Nintendo carts. If Nintendo carts were worth anything, they would still be sold as Nintendo carts. One could argue that NES ROMs take the place of other newer games people could or would be playing if they had no NES carts to take up their time and energy. That might be a valid point, I don't know. In any case from a legal standpoint you are right, NES ROMs are not yet public domain so far as I'm aware.

However, if I concede your point, my original point stands. If you believe that NES ROMs should be protected, you must agree that new games should be protected even moreso.