For any (large) group communication space, there is always a need for (some) moderation. See http://www.codinghorror.com/blog/2005/05/a-group-is-its-own-worst-enemy.html for some discussion for instance.
Imagine a line representing freeness of speech, with 0% at one end and 100% at the other end (the word freeness here meaning lack of any restrictions). Where on that line would you put a cross for the optimum value of free speech? There are no countries in the world (or any society though history) that allows 100%. There are typically many things you are not allowed to say, like uttering death threats, crying fire in a theatre when there is no fire, in a court you are not allowed to lie (think about how enormous restriction of free speech that actually is), etc.
The point is, exactly what the "optimum" value of free speech is is always a subjective opinion, and it is always less than 100% (although normally quite close).
Also I assume you are a man that have not been exposed to the darker side of the this problem which apparently is significant (I am also a man so I have neither a first hand experience). I recommend you to watch the documentary "Uppdrag granskning: Menn som nÃtthatar kvinnor " (men net hating women), http://www.svt.se/ug/man-som-nathatar-kvinnor, if you can find a translated version (https://sv-se.facebook.com/granskning/posts/10151724543289883).