> I don't see why a company that refuses to add to a GPL project has a "decent change" of releasing their code under a more permissive license.
Because upstreaming a patch once is cheaper than maintaining your own proprietary fork forever. It externalizes the effort of maintaining it in the future. That's the point that the article makes. And it's true in my experience. My employer allows and encourages me to contribute back to our dependencies. Those aren't the core of our business and our competitive advantage
For a library I see what you mean, maybe that's the main case you're thinking about.
But for applications, if they are willing to invest the costs to rewrite the GPL option I don't see how your argument makes sense.