tat tvam asi wrote: who ever allows the most free speech will likely come out on top in a larger competitive sphere. Whoever is branded as anti-free speech, and one sided censorship, will almost definitely wane in popularity. And take the related monetary hits.
Probably it's not that simple. The revenue comes from ad revenue. 4chan definitely has the lowest standards for decent behavior and truthfulness, but most people don't want to go there (except, perhaps, like one takes one's children to the zoo to gawk at the beasts). The idea that I don't have to worry about verifiable, provocative lies being spread on facebook definitely makes it more attractive to me.
Ordinary human community is not libertarian. People who want to be anti-social can go do it by themselves. If anything, most people are too intolerant and tribal, and that's where the internet echo chambers are finding their niches. The biggest social problem for our time is the one of reaching across those boundaries which so easily become barriers.