There was one weakness in RMS theory: copyleft was not part of the four freedoms he theorised. Business-compatible licenses like BSD/MIT or even public domain are “Free Software” because they respect the four freedoms.

But they can be privatised.

And that’s the whole point. For the last 30 years, businesses and proponents of Open Source, including Linus Torvalds, have been decrying the GPL because of the essential right of “doing business” aka “privatising the common”.