You seem to be confusing "free speech", the concept, with "free speech", the legal right.
Most codifications of the legal right limit themselves to protecting against certain types of government interference.
However, the concept itself is absolutely not limited to contexts where censorship is imposed by a government. To try to impose this limitation is 1984-style thought policing that tries to remove existing language to control what can be said.
I'm not talking about some colloquial meaning, but the core meaning of the concept of "freedom of speech".