I would not call it a mess. I run Ubuntu on Lenovo X1 Carbon and Asus Zenbook UX31A and on both machines all the software that I run except Steam work just fine.
It really isn't. I've been running fedora with gnome-shell for 3/4 months on hidpi and most things run fine. The applications I had problems were Chrome, it's solvable with 200% zoom, although the UI remains small and Netbeans, here it's more serious because the UI is more important than on Chrome. Another problem is the impossibility of having different scalings on different displays. Everything else that I've needed runs fine and It it's getting better with each gnome-shell release since 3.10. And anyone can try it before buying a display/laptop just by running the scaling command given on the article. In my opinion/case the sharpness of the fonts/icons/ui outweight the small problems that I've had, but using Netbeans and Chrome aren't mandatory to me.
How do you survive with UX31A's touchpad in Linux? On my UX32VD it's the most horrible part of Linux experience (also battery drained while idle in 2 hours (2 SSDs) doesn't help)
I have a UX31A and my experience is like yours with Ubuntu 14.04.
Only quirk I have with the touchpad is that on Windows, with 1 finger idle on the touchpad and another finger moving the cursor would still move with the moving finger. On Ubuntu, the cursor remains stationary any time there are two fingers on it. I probably would not have noticed it if I weren't already so used to the Windows functionality so it isn't a big deal at all.
Right, you shouldn't have to switch operating systems to get the benefits. It seems perfectly reasonable to expect the display subsystem of your preferred OS to support HiDPI mode, however it chooses to do so.
And OSX is not Linux. I don't want non-Linux OS.