Great post, @sostrin.

At every school I've ever attended, every job I've ever had, every social media platform I've ever joined, every church I've been a part of, every trip to a store or cocert or event, even every family get together, there has been at least one person that seemed to be there for the sole purpose of scamming, belittling, arguing, bullying, harassing, or in some way or another making everyone around them uncomfortable or affecting their experience in a negative way.
But it's ultimately up to us to decide if these people get to steal our happiness, our peace or our good time.
Normally, recognizing them and their motive and choosing to ignore them does the job. But sometimes a few strong people have to stand up to them. Bullies are loud, but usually weak, so they tend to back down and hush up when they find out that their nonsense isn't going to be tolerated.
I think the number of good people here outweigh the bad so drastically, that the good with big voices can shut the bad down without a appointed governing body.

The scary thing about making a list of things someone can't do, or can't say is that the list of specific infractions would be forever growing, and generalized rules limit the good along with the bad.
Besides, who gets to decide what okay and what isn't? Will everyone in the community agree with the rule makers?
I think this platform can selfgovern effectively.