The amount of jackassery in a fandom is a function of the fandom's obscurity.note A unimodal function, that is, but if we start off with a word like "unimodal", pop! The readership disintegrates.
This means that the proportion of jackasses to normal people sharply increases with the obscurity of the fandom until it reaches a peak, then sharply drops off again.
For fandoms not too far from the [...] [tvtropes.org]