What I can see is a fairly clear indication that they do not want contributions from people whose politics differ from theirs. I would also question whether government funding of a project with political policies about who can participate is appropriate. The political stance is also rooted in a particular culture so is unwelcoming to people from other cultures.
Of course people can political views and preferences, but they presumably have some aim in mind when making that statement in the README. What is that aim?
The GPL variants are the antithesis of politically neutral.
Because you can have preferences while not restricting legal rights.
This is the same FSF that in the past has refused contributions from people whose politics include "I would like this software to run on my windows/apple/other proprietary platform". They're extremely political.
"If the point is to promote Free Software, we do ourselves a disservice by making our Free Software work better on a proprietary system than a Free system. Let's include this support when it works on the Free platforms as well."
FSF is political, but only about Free Software. Their goal is to promote it, and I think RMS has shown very clear thinking in this regard. I don't love the decision/outcome (someone did work to make something better and it was rejected), but I get it in service of the larger goal.
To flip the pschology, you could imagine a world where Emacs did way more awesome stuff on Windows and Mac, and the ensuing HN discussion where the obvious snipe appears a dozen times: "lol they keep talking about free software but their own products work better on windows lol".
I don't see how that's related to the topic or issue being discussed though. If you're a maintainer you decide when to shut down a discussion. Someone is annoying/creepy/difficult and wants a feature? Let them fork it, eod. Every escalation afterwards is basically just trolling or harassment.