I don't think you've made a point about his abilities. I do think you've restated his proclivities, which reinforces the basis for the quip.
There's a reason there's a subreddit called "Stallman Was Right", and it's not that he was shotgun blasting opinions and landed a few of them. It's because he has a systemic understanding of the incentives our system sets up and is able to project decades into the future about how those incentives will play out.