If anything, my experience is the opposite. The initially best communites soon develop some kind of clique identity, and set up arbitrary rules about what is al

If anything, my experience is the opposite. The initially best communites soon develop some kind of clique identity, and set up arbitrary rules about what is allowed and what is off topic. I'm not talking about trolling or abusive behavior, but just content that is not aligned with what the clique considers "fun" or "on topic". In the case of Wikipedia or Stackoverflow, this takes the shape of deletionism. In addition, if you give anybody power in an online community, it seems to go to their heads. They develop a hall monitor mentality. It is even worse in the mentioned sites since almost everybody can perform moderational tasks and thus feel like they should hold up the rules. Rather than "censoring" or "curating" (depending on your viewpoint), I would much prefer a good search function and separate categories. Disk space is cheap and the internet is infinite. Reddit does this pretty well, despite constant moans about the quality. There is an area for almost everybody and every topic, whether you want a clean garden or 4chan or something inbetween.