[bolognafairy]

Linux is not a “major desktop operating system”. Let’s be intellectually honest here, particularly because you’re using the number “3” to bolster your argument that Apple is being negligent or unfair or whatever. Be annoyed at Apple for not ‘supporting Android’ or whatever all you want, but let’s not pretend that Apple isn’t paying a very justifiable amount of attention to desktop Linux. What next, iCloud.com doesn’t load properly in Lynx?

[MacsHeadroom]

Estimates from earlier this year are over 60 Million Linux powered desktop PCs globally.

That's not a huge portion of total market share but is still major by some measure.

[pixelmonkey]

Exactly. And I also like to remind the Apple fans that Linux's desktop OS market share today is around the same share macOS X had in the period 2002-2010, when Windows was completely dominant and before the iPhone turned so many into macS desktop users. I also like to remind them that the perspective that iOS and Android are both dominant mobile platforms is very US- and Canada-centric. In the rest of the world outside of the very richest nations, Android is dominant. And in many poor areas the world over, Linux desktop is used if for no other reason than to rejuvenate used hardware and avoid software licensing fees. So Apple knows exactly what it is doing when it avoids cross-platform development.