I never realized visiting a website required me to "sacrifice my freedom"!
If you did, you'd see that he has a perfectly valid point about how the effect of non-Free licenses, combined with minified (and therefore effectively unreadable) code, especially that which uses dynamically constructed elements, is hard to read, hard to share and hard for the community to improve. The tone of the article is pragmatic, reasoned and doesn't jump up and down crying 'Injustice!' or waving a placard. Much as you might hate this, it's a reasonable technical argument that follows logically from the concept of Free Software itself.
If you want to argue against Free Software on its merits, knock yourself out. I work with both proprietary and Free software all the time, and I see the benefits of both. But when you start pitching a fit and belittling someone else's calm, reasonably stated points without even attempting to address the logic, then you've lost any credibility. Honestly, you can ridicule Stallmann all you like, but you might want to consider what you look like to others as you indulge in this kind of adolescent, pop-collared frat-boy humour.