I wouldn't say having to confine your speech to private quarters where word can't get traced back to you is being able to "speak freely". If you can't write a newspaper letter to the editor, or post an update on Facebook, without your creepy employer stalking you and disciplining you for it, you aren't able to speak freely.
At any point in history, if you wrote a "Letter to the editor" disparaging your company or boss, you'd most likely get fired. How is posting on a public web service different?
Because now you risk your employment by writing a letter that isn't about your employer at all. Anything your (prospective) employer doesn't like is verboten. So people deliberately circumscribe their speech.
