Thanks for the article. Interesting read although very dated now.
My takeaway is not that higher resolutions are moot, rather larger screen sizes at close viewing distances are encouraged. They even link up what to buy with links at the top of the page disguised as a education tool. Lol.
In practice, I install PJ screen combos between a ratio of 1.1x-1.3x diagonal. Depends on room. You simply cannot plan seating for a group of viewers closer than 10’ and expect a comfortable experience from an integration standpoint. (Ive seen ot done on AVS, but those installs dont make sense for many reasons.) This yields a very comfortable screen size and also nearly optimal stereo placement for L/R channels flanking the screen. This puts my installs on the fringe of “barely noticable” in some cases.
I can tell you this simply is not accurate for more than one reason. For one, users do not view test patterns or static charts. We do for setup and calibrating, but after that not. Also, 4k content is mastered to a different color and brightness scale than 1080 rec. 709. Instant tell. Also, sitting at distances they recommend will cause severe eye fatigue in darkened rooms unless the screen brightness is reduced..... This reduces perceived contrast and also defeats the purpose of UHD grading.
I put very little stock in these kinds of articles. In my latest effort with a 110” screen, 4k is noticably better than 1080 from 20’ away at the pingpong table.
Many variables in play other than angular density of pixels. It is foolish to plan a setup around maximum perceived quality..... I would have to install a puke pail at each end of the couch for viewers.