Well, I wouldn't say it's being "micromanaged" really. It's being managed. OS is a private site, so to equate it to a "real world" setting, it's like any private property...freedom of speech doesn't apply.
That's the reason for things like a "Terms of Service" agreement. Much like a "code of conduct" for private clubs, groups, businesses, etc, it outlines general guidelines for acceptable behavior. It grants them the right to take what they deem to be appropriate action for behavior they feel diminishes their property's intended purpose or value.
While I understand your sentiment of "say what you will and defend yourself", the "let it fly" mentality leads to a free-for-all of back and forth nonsense, devoid of any information being gathered or distributed. It causes unnecessary headaches for people who simply browse through for updated news...let alone people who come for discussion.
So, I can agree it's at least partially about control, but not just for the sake of it (for the most part, at least). It's control to ensure the site is up to the standards of the intended use.