I mean for now there is a fashion among contributors to keep software open-source, but they don't like it as obligation. (Where "contributors" include ICs, but are really mainly businesses these days.) And the notion of "universality" is in fact more about forsaking my right to require the software to remain free. Why would I need that again? It seems that when thinking about progress/ROI open-source turned out to work very well as a fashion, what's wrong with it being a legal obligation then?
List of variants of BSD: https://fedoraproject.org/wiki/Licensing:BSD?rd=Licensing/BS...
The weird argument above was that there are apparently too many variations of the GPL (even though there are many, many more BSD and MIT variants). So I said, stick to a single GPL variant. And then you ask if you can mix GPL versions together.
Enter GPLv3 which wasn't even compatible with the unmodified GPLv2 and to Landley this made it no longer a universal receiver. Couple that with his disagreement over using the GPL in BusyBox to leverage source code from vendors, he created ToyBox and the 0BSD license. He sees the 0BSD license as a universal donor since GPL is no longer a universal receiver.