[necovek]

There was a quick option to change subpixel layout way-back-when in Linux (GNOME 2.x series), eg. a quick search gave me a screenshot at this page: https://askubuntu.com/questions/88528/how-to-switch-on-sub-p...

Today it seems it's hidden as a dconf option:

  $ dconf read /org/gnome/desktop/interface/font-antialiasing
  'rgba'

But this is an issue that applies to VA panels as well (cheaper than IPS, worse viewing angles, but better contrast ratio), and I have a 27" 4k VA screen that works just fine with it turned on in Linux — text is so much clearer with it on than off, and attaching a MacBook to a 4k screen at 27" or 32" IPS makes me hate MacOS for killing subpixel rendering off.

As for "retina" resolutions, I've tried 24" at 4K as soon as it came out (with that Dell monitor that required 2 DP 1.1 connections for 60Hz IIRC), and turning subpixel rendering off made text and lines jagged — that was ~190 ppi at a normal viewing distance with vision corrected to better than 20/20 (which is what I usually have — can't really work without glasses anyway, and worse correction leaves me with headaches). For the record, 5k at 27" and 6k at 32" is roughly ~216 ppi, so not much better than ~190 ppi: subpixel rendering probably achieves 2x the increase in text clarity for those not sensitive to colour fringing (I am not).

So, subpixel rendering is really not an issue on any displays, but Apple will happily tell you what's the limit of your vision and upsell you on their monitors.