And GP's point is that a) statistically speaking, pretty much all of the users of software today are non-developers, and b) these users don't care about the freedoms that the GPL seeks to protect. Even in the small subset of users that are developers, the popularity of permissive licenses indicates that most would rather just use and open up source code without worrying about restrictions imposed by others or imposing restrictions on others out of some sense of morality.
The upshot is that the GPL just creates additional friction for developers in the pursuit of ideals that, statistically speaking, nobody really cares about. This is why it is misguided.
The primary purpose of the GPL is to insure that users have the freedom to modify and redistribute the software they use should they choose to do so. Whether the user does so or not is irreverent. That's why I don't think it's a matter of whether end users care, or how large of a percentage they form of the overall user base.
Developers who decide to license their work under the GPL do so to safeguard their own freedom and the freedom of their users. To that end, I think the GPL hits its mark.
The upshot is that the GPL just creates additional friction for developers in the pursuit of ideals that, statistically speaking, nobody really cares about. This is why it is misguided.