Your definition of 'wrong' is certainly agreeable but not exactly relevant in this situation. Yes, technically RMS was just being nitpicky, but in the context it doesn't matter. The comment was inappropriate and any person in RMS's place has to understand that because of their high profile everything they say/do can and will be used against them. Those are the rules of the game (public relations), and if you don't play the game (like RMS), the game will play you.