I'm confused why you use the phrase "GNU/Linux" but not "free software". I've never seen someone use that combination before. But as to your point, not all fre

I'm confused why you use the phrase "GNU/Linux" but not "free software". I've never seen someone use that combination before. But as to your point, not all free software licenses are copyleft. The MIT and BSD and Apache licenses are all proprietary-friendly licenses. And as for requiring to extend the GNU/Linux ecosystem, I don't think that's true. It just looks like they've implemented syscall compatibility with Linux (something that FreeBSD has had for donkey's years and SmartOS has been working on for the past few years). Neither of those technologies resulted in more software specifically for GNU/Linux.