Who cares? If you individually happen to be red-green colorblind
It doesn't matter that you're 1.78 meters and 73kg
Whether you prefer a different distance or have sharper or weaker eyes doesn't matter
Nothing about how you use it or what you put on it.
that metric is not based on YOUR EYES or YOUR USE.
Show me where I'm talking about user's preference?
seriously ...
What's displayed on screen will change the distance of use. That you refuse the discussion is beyond me.
You are only repeating the same things, you deliberately stick to always the same arguments, carefully omitting to answer to some points I make. I've not seen contradiction or answers in the elements you expose (not subject to discussion when simple facts that won't be false).
wtf
How relevant is it to use as reference Home Theater norms and HDTV screens with all the same resolution at different sizes and then relative distance, when we're talking about computer/tablet/phone screens? Desktop OSes and mobile OSes have different conventions and usages, their users are closer to their screens [relatively], their UIs are designed accordingly, for screens with pixel sized (at least in the Apple world) proportionnally: 160-130 130-110-100 ppi with 2x variants.
Why only consider the hardware aspect, and never the software? the answer "because it's not relevant" is not receivable.
From my first post in this thread:
Used as a 960x540 pts screen (for example. 2x is only more convenient), with all the right technics to use all the pixels, an HDTV will probably display content (other than a movie/TV show. Text in particular) allowing the user to be at a distance suffisant to qualify it as retina. Not if it's used as a 1920x1080 display, as well as the 21.5" iMac isn't retina
It doesn't negate the intrinsic minimal distance of a given screen at which individual pixels become indistinguishables.
Without software/content displayed, a screen is a black sea of pixels, or specs on a box.
The 'retina' qualificative means you'll be able to use a screen at the distance pixels become invisible in 2x HiDPI mode. Not every screen can be used for an iOS or an OS X device, the software/UIs built are limiting as they were exactly built for specific pixel densities and relative distances.