Compared to permissive licences (from the user's POV), GPL is merery a guarantee that a proprietary fork won't left you behind in the dust overnight. That's a rather strong guarantee that most people (including myself) don't need. I'm fine with a "plain" guarantee to fork the last free version. In exchange, I usually get better, well-supported software with more corporate contributions.

> Apple has famously used a lot of time and money to rewrite GPLd thengs. This is the goal.

As an aside, that's a terrible goal. Rewriting the same projects over and over is a waste of human potential. We could be solving unsolved problems and actually making the world better, instead of pursuing this weird and misguided notion of "fairness"