You were bringing up a interesting/intellectual point until you mention the word free. At that point, either you are pointing towards a tribe of thinking, or simply ignoring the massive amount of Philosophy that has been written around the concept of freedom and the many and large volume of thought that has been written about it. John Locke wrote 400 years ago a definition of freedom that fits what RMS says, and its not without reason that RMS often says that the word liberty is a better word since its less ambiguous, except for in the US where liberty has been associated with a political party. GPLv2 even call a clause "liberty or death", rather than "freedom or death".

Is it really that wrong to use freedom and liberty as two interchangeable words? Having read some philosophy, even those trying to define the words often use both words. As an example, "Persons have a right or liberty to follow their own will in all things that the law has not prohibited" and "Freedom is constrained by laws in both the state of nature and political society".