I really think you are selling Stallman's pragmatism short. While he very laudably tries to live by his own principles as uncompromisingly as possible, it's clear that he sees social systems as things to be engineered, with moral pressure being but one tool of many. Certainly his grasp of such systems is not perfect. But I think he's done astoundingly well for a reclusive, autistic nerd with no social skills.
I think the subject at hand is different from what you are writing.
What you are saying doesn't apply to the debate between permissive licenses and copy left licenses.
You can't have freedom (or at least won't have it for long) if others have the freedom to take it away from you.
Copyleft gives you every possible freedom, except the freedom to withold those freedoms from the next person that comes along. It's not just a way to give freedom, it's a way to enforce it.
You could say that anarchy, where everyone is free to do everything, is the ultimate freedom. Then you step out of your bunker and get shot because someone wanted your shiny watch. So we trade a few freedoms in exchange for being able to enjoy the rest of them unimpeded.