That's true. And actually something else occurred to me. If you ban all the trolls and all the critics you end up like Ralph does with no one in chat except people spamming gifs. Treating your stream like your home instead of a public square means that no one will bother to comment. Oddly enough if you're a left-aligned Big Tech company this isn't such a problem. You always have a few pet streamers with the right opinions like The Young Turks, and the networks who'll provide content, your equivalent of Ralph's Gold Star Callers. It'll be an echo chamber but not such an obvious one.
In retrospect, I think this is one of the things that made the Killstream impossible to listen to. Ralph lost the ability to laugh at himself and banned anyone else who did. With the end result that we're talking about him here rather than engaging with his stream.