No. Your linguistics prof is absolutely full of shit. Or well, we don’t say that north of the Mason-Dixon line. I can’t speak for the South.
Good, because freedom fries sounds ridiculous! I mean funny, yes, but the explanation was dumb. Something about Americans having some problem or other with the French and thus changing the name from French fries… What?
So, there was a call for them to be called ‘freedom fries’ (also freedom toast and freedom dressing) after the French refused to back the US in our invasion of Iraq. But, as we all know, Dubya (that is, Fmr. President George W. Bush) was borderline batshit, so it never really caught on. At least not in any of the states that I have lived in post-9/11 (which is to say, California, Massachusetts, Minnesota, North Carolina, Colorado, and New Hampshire).