Many find comfort in denigrating aviation just because they didn't get what they wanted out of it for whatever reason. Many of those are wannabes who have never had any pilot job. Some are disgruntled experienced pilots. The common denominator of all of them is that they feel better about themselves when pointing out other people's choices as "wrong" (without suggesting any better course of action) and when trying to convince themselves that there was nothing worth fighting for by trying to convince others therein.