They always go after people for “pretentiousness” and so does their audience.
But they aren’t being pretentious. Of course they believe in their own interpretations about a film, but they aren’t claiming that their opinions should matter to you. And remember that time they called other YouTube critics “pricks”? In the next episode they bring up how many people got mad at them and Rich blatantly says “I’m a prick.”
They do claim that people who don’t hold their opinions are stupid and simple-minded. That’s pretentiousness in my book.
And to bring up the whole audience issue, I don’t think their fanbase has nearly as many blind followers as you seem to believe there are. People repeating jokes or generally agreeing is perfectly normal.
Judging by RLM fans’ willingness to love or hate a film based entirely on the RLM stance without even having seen it, I’d definitely disagree with you. You yourself have done that on this very forum.