The whole discussion is a hellscape, and you (should, by now) know that it's not our role to adjudicate on the correctness of anyone's arguments. But “bootlicker” is, by design, one of the most demeaning terms of abuse that ever gets used here, it's not asking much, at all, to expect people to avoid using it. That account has contributed little of substance, so it's not as if there was a track record of quality to indicate this was a momentary lapse.