Their game is to not address, and to try to shift attention away from their failure to address criticism of the irrational ways in which they are using their words. And, lo and behold! What's one way they love to try to silence said inconvenient criticism? Why, they love to reflexively throw at it the word, "semantics," hoping that so doing will somehow have a belittling effect against their critics. Over the years I've asked numerous people, in various contexts--people who have called my annoying questioning of certain ways in which they have chosen to use certain words they have chosen to use, and who then have tried to lash out at me for it by calling my questioning, "obsession with semantics," and such--I've asked them exactly why they imagine that the word, "semantics," has some sort of use as a pejorative. And, you know what? Not a one of them has ever even let on like they saw this question; much less has any of them ever tried to answer it.
Semantics, really, is just a concern with questions of meaning. Nothing wrong with that. When you say something, and someone asks you critical questions so as to try to find out just what (if anything) you mean by it, and you find yourself cornered into reacting to their questions by saying something like, "You're just obsessed with semantics!" you might want to pause to give some honest consideration as to which of you has the upper hand in the situation: you or your critic/questioner.