I disagree. People talk about 'wrong behavior' pushing people away. In reality, posting freedom lets the community decide what behavior is wrong and push it away. Internet is about the last place you can have freedom (for now), and the sterile, mercantile corporate culture of 'everything has to be nice and marketable' is seeping into everything, and ruining it. Can't say bad words, can't have bad thoughts, can't express yourself. Long lists of rules suck, rules are often vague, often on purpose, so you can be banned on a whim. Bans in general are lame, there are probably better ways of punishing unwanted behavior, like making fun of the guy. My personal ideal ruleset I've used in a chat to great effect is: don't turn conversations into pure insults, no porn, no politics, no illegal stuff. Simple, straightforward rules give people freedom to discuss things, however they want. Sure, it pushes away people not open-minded enough, but wouldn't they leave eventually anyway, once someone slips up? It creates pure, authentic, human discussion, instead of something sterile, formal and artificial (kind of like what I'm writing right now), where you have no ambiguity, having to ask yourself 'will posting this get me banned?'. Strict rules, especially bans on swearing, will just make people tip-toe around what they really want to say and posts will be passive-aggressive, which, in my opinion, is a lot more obnoxious than someone openly calling you a bad word, and you will have even less ambiguity, not having to ask 'is he insulting me?'.
In addition, any place of power, however minor, can, and will, eventually, be corrupted. I've seen countless communities die, because the staff got filled by incompetent, petty people or straight up sexual predators. They never recovered. As for this specific forum, community seems nice, but the rules are a bit too restrictive. Also the sample conversations are pure strawman.
People need to learn to be respectful to each other, but also to take a banter or an insult once in a while, without admin involvement. People are way too sensitive about words on a screen from someone thousands of miles away, who they will never meet.