You have some evidence for this?

Only some personal experience and general intuition. I don't think anyone, even Eliezer, is going to argue that zero meta discussion is optimal. The question then is how much is optimal. It is possible that a weaker version of my statement like starting it with "it seems that" might have been helpful.

In this thread and the perfectly superfluous other thread you made for this topic, I have observed a tendency to state ex cathedra beliefs on the nature of communities and what mechanisms are necessary for their survival.

I agree that there's a fair bit of stated beliefs without much evidence all around, although I'm puzzled by your description of the other thread as superfluous.

Do we have any reliable authorities on the sociology of internet forums yet?