I can think of another application of your/Hanson's idea. It always seemed to me, was that for all the handwringing over bad comment field culture or low quality content, site owners would rather have that than give up a finger of control.

Rather that try to define quality and think about the processes which could bring it about, they have a "I know it when I see it" attitude to quality. They value their personal discretion to promote, bury, editorialize and censor far higher than actually being a high-quality truly open forum.