Laws regulating free speech by the state, or the absence of them, are irrelevant to the question of "free speech" on a private discussion board.
We can only answer the question, Should all contributions be allowed? by first asking, What do we want from a discussion Board?
I can only speak for myself, but what I want is, first of all, an audience. I want to think that thoughtful people are reading what I have to say, people whom I have some chance of convincing, if they disagree with me. And if they already agree with me, I hope that we will be able to reinforce each other's belief by exchanging information.
Second of all, I want to find people who do not agree with me, but who can give me a fight. I want to find intelligent opponents who will challenge my thinking -- because either I am wrong, and need to change my views. Or I am right, and need to find out the best case that my opponents can make, in order to be able to answer it.
Thirdly, on the social level, I enjoy meeting people who are interesting, and who, if they lived down the street, might become friends. One of the wonderful technical developments of the last couple of decades has been the internet with its possibility of extending our lives beyond the physical confines of job and neighborhood.
So what I want from a Discussion Board is that it attract interesting people.
This means: I want the administrators to exercise censorship: drive away the trolls, the people whose contributions are simply personal insults, the unpleasant and insane.
Because like attracts like.
In theory, you could have a Board with lots of morons posting, and also, mixed in, the non-morons. But in practice, who has time to sift through every thread and ignore the eruptions of angry teenage boys who can't get dates, the psychopathological, the autists, the neo-Nazis, the people foaming at the mouth from Bush Derangement Syndrome, etc.
The more you have of them, the less you will have of ordinary people who know how to be courteous even to a political enemy. There will be a kind of Gresham's Law of Discourse: Bad contributors will drive away the Good. I saw the Protest Warrior discussion forum absolutely wrecked by cretins from both left and right who just flung feces at each other.
So I hope the Administrators here will use their power to banish trolls and persistently sub-standard contributors (not in terms of content, but in terms of decency) ruthlessly.
"Better fewer but better," a slogan of which I believe Lenin was fond, and which the USMC practices today.
