Looking around, these displays have been available since ~early 2014, and anybody who didn't know they were coming would have had to be in deep ostrich denial mode.
Being around and being in the right hands are two different stories. Last time I checked OS X was the only operating system that properly handled very high resolution displays (I know that Windows 7 and 8.1 did not), and I don't expect Linux developers to be super far ahead of the Windows curve either.
If I'd known computer science was going to be like this, I'd never have given up being a rock 'n' roll star. -- G. Hirst