It isn't about freedom of speech. It's about having some goals and principles set. Every single forum that is moderated (99%, and the other websites are not worth mentioning) has some "freedom restricting" rules set.
This is our new rule and it's described and open for voting and discussion here: meta.opi.wiki/discuss/110080/Guideline-an-OpiWiki-opin...ast-one-argument. Feel free to reply there.