> legitimate criticism isn't racist and no one says it is
Free speech means freedom to express “illegitimate” views, “the fullest liberty of professing and discussing, as a matter of ethical conviction, any doctrine, however immoral it may be considered”. No one has reached a universal agreement on what “legitimate” criticism is. Of course there are often prevailing societal opinions, but those change with the society. Eg. the Federalist Papers were largely written by someone who was literally labeled “illegitimate” by society at his time (and were full of slurs, stereotypes, etc.¹). Someone who got killed in a duel — the meaning of civility changes with the civilization. IMO ours is at a fairly high point at the moment (in part because of the value placed on tolerance for differing values), but it’s only a matter of time before it inevitably collapses much like the Greek and Roman ones before it (likely in part because of intolerance for free expression).
If your idea of criticism is something like using a slur or stereotypes to make an argument then it is not politically correct.
What's the criticism you want to give but feel like you can't?