IMHO, the point being missed is that trained professionals in any field are often beset by non pros who automatically feel some type of kinship because they do as a hobby what the pro does as a vocation. "Hey, look, I've got a camera too!" What they often don't realize is the pro has technical knowledge and experience far beyond what they have.
I'm a pastry chef, so I'm often approached by people who have no formal training, but lots of recipes from grandma. Mostly what they produce is competently done, but far from professional standards. They usually have a different opinion of their work. So what do me and my pastry chef friends do when we get together? We share our stories about these family members and friends, and we do it in a mostly humorous, often sarcastic way. Do we mean any harm? No. We don't hate or bare malice towards these people. Are we talking down to them? No, but I understand where it could be interpreted that way. What we're doing is venting over a type of behavior/attitude that gets thrusts upon us with regularity by people who don't have the technical knowledge or experience that we do, and don't understand the difference that makes. That's all that blog is, venting. If you don't vent, sooner or later you go to work for the Post Office and buy a gun.