P.S. I note in the linked-to article, https://writing.kemitchell.com/2019/03/09/Deprecation-Notice.html,
Several lawyers came together, in GitHub private repos
And indeed there seems to be no public record of this drafting process, at least not one that I could find. This seems diametrically opposed to much of the philosophy underpinning copyleft-next and its development, expressed in part as the Harvey Birdman Rule: https://raw.githubusercontent.com/richardfontana/hbr/master/HBR.md