I understand your point. But even if you will read the ROM, you'll have to
write it back in order to use the changes you made on real hardware. That
will basically mean using an expensive flash-cart or making a repro cart
(which is probably even more cumbersome).
And while it is obvious that non-free software is creating numerous problems
which are all solved by using free licenses, I still believe that the issues
with games, especially on old consoles that don't have internet connectivity,
are less severe than with normal programs that run on our PCs. It's only a
theoretical disadvantage and any kind of malfunction is just a bug in a game.
How bad is it that your games have bugs? It's not a threat for democracy
after all. The ethics are still the same, but the real threat is much, much
lower.
And I'm not even commenting on what you said about copyright, there is no
arguing that.
