Only on the part of those who have never been exposed to what a DIR class is really like. My experience with DIR training was that the instructors encouraged questioning the system, and particularly encouraged questions that began with the word "Why" ... they really don't want people to just blindly accept the system without understanding the logic behind it.
There is a rational reason behind every component of the system ... whether you accept it as a valid reason or not is really your choice, but there is a great deal of emphasis in the training on making sure you understand why it is what it is ...
... Bob (Grateful Diver)
In fact, the first GUE instructor I met, Ed Hayes, asked the attendents of a workshop how we do certain things and asked us to explain what for example controls buoyancy. He then provided his (organization's) take on selected topics and not only provided an explanation of why things are done a certain way but also provided proof in the water. There is not much you can and should argue about things that work and make sense.
When I had mentioned that I was going to this workshop I got exactly the same response and attitude at my LDS as the OP described. 'Gear Nazis' was the most colorful prejudice.
Similar to the OP, the reality was that I met a group of extremely competent and welcoming divers - and I arrived in a jacket BC. I was not ridiculed or burned on the pyre because of that; just reminded that the afternoon DPV tryouts would require a crotch strap and therefore borrowing of a BP/W. Boy, was that a tough sell
I arrived and dove in a wetsuit with a HP100 steel tank. Again, no eye rolling or ridicule just a friendly and detailed explanation of what the potential pitfalls of this combination are.
(I post this not because I am holding my breath that the DIR bashers on SB will ever see the light. Never, ever hold your breath anyway

. But, for the benefit of new SB members, we still can and should hold facts against negative, unsubstantiated propaganda.)