I saw simonize’s statement as less “projection is a type of empathy” and more “projection is what assholes have instead of empathy”.
They are, as you say, almost diametric opposites. But they are on the same axis in that they both feel like “I know what’s happening in that person’s head” — but where empathy is “… because I am making an effort to model their mindstate”, projection is “… because I am assuming that their mindstate is the same as mine”.
