Political correctness (n.) is a morally just stance which translates politically and socially as "Watch what you say and don't give offense to anybody." This isn't a serious definition of diversity.
Political correctness (n.) is the misguided conflation by those who seek an extension of 'rights' with a demand for an abridgment of 'speech.
Political correctness (n.) is an approach to language which, through its excesses, threatens to make people weary of the good causes of underserved groups.
Political correctness (n.) is rooted in a paradox where something called 'diversity' is secured by insisting on something definitely recognizable as conformity.
Political correctness (n.) is grounded on the idea that if one claims that something is 'offensive', it is as if the assertion itself has automatically become an argument.