As for moderated vs. unmoderated threads, the main issue is S/N-ratio. It's possible to buy sockpuppet work for $0.12-$0.20 per message. Just to take an example, NewLiberty posts here and the opportunity cost for him to write these messages is certainly about $100. It is possible to inundate his reasonable and insightful messages below a pile of junk at a price much cheaper than it is for him to write them. This is an economic attack which wears down the good posters so that in the end only the junk remains.
(self)Moderation is a way to mitigate it. If you feel your contribution is not welcome, you can refrain from posting into such threads and do not lose anything. NewLiberty's readers gain by not needing to wade through the pile of junk when they are interested mainly in NewLiberty's contribution and the insightful responses to it.
I suggest you open your own private forum for you and your supporters to enjoy "insightful" discussions free from this "pile of junk" (as you call it) all the users with differing opinions post here. This way you can enjoy "clean" discussions with your supporters and fans while giving this place relief of the Monero invasion at the same time. It would also cause you less work as you wouldn't have to delete/censor half of the posts in your threads. How about that? Your current approach basically screams for the trolls to come and troll against "the great self-proclaimed teacher" imho.