Matt needs to reread 'The Cathedral and the Bazaar'. The different between the "free software" and "open source" discourses has never been copyleft vs. non-copyleft, that's a separate debate. It hinges on whether coders are a subset of users, just as writers are a subset of readers ("the bazaar"), or whether they are the digital equivalent of medieval clerics, who can legitimately deny users the ability to read the code of the software they use ("the cathedral"). https://www.techrepublic.com/article/fair-source-licensing-is-the-worst-thing-to-happen-to-open-source-definitely-maybe/
What Matt doesn't want to accept, is that #copyleft is precisely the answer people are looking for when they try to apply things like the #FairSource license, the #CommonsClause, or the #PPL (Peer Production License) to software. They want to protect the software commons from extractive capitalists, who don't want to contribute back to the pool they draw from. Copyleft was created to achieve exactly that protection of the software commons.
To be fair, the article I'm responding to was written in 2016, and Matt's CV is full of exactly the kinds of extractive capitalists people are trying to protect their commons from. Not surprisingly he rails against copyleft and the AGPL just as hard as he rails against the Fair Source license. But in the case of AGPL, I think it's Matt who needs to accept that the world is moving on.