I have been waiting 10 years for for resolutions to finally increase... I ran 2560x1920 back in the CRT days and it was a painful wait before LCD's finally did 2560x1600 and were acceptable resolution for me to upgrade and shortly after that went to 3840x2400 on a smaller 22 inch and literally 9 years after that they *finally*, *finally* are getting more 4k displays.
Some people have good vision and don't have to 'blow things up' to see them. On the 39 inch side I could easily still read stuff at default font sizes even if the display was 8k at that size.
I agree,.....
Although I prefer to run at 3840x2160 most of the time on both the 28" Samsung and the 39" Seiki without scaling I can see how some people would like to run scaling. In OS X, the scaling modes look really quite good IMO. So if someone wants to run a scaled / effective 1920x1080 because it looks good to them for some things I don't blame them. This IMO opens the door or lends a great deal of legitimacy to 24" 4K monitors for some people in some cases. 24" is smaller then I would personally prefer though.
I think some people just have trouble understanding / acknowledging anything that doesn't suit their specific wants and needs so they just don't get it.
BTW, I haven't had the opportunity to run red text on a black background on the Seiki yet but I will make a point of trying it now. I have a fairly good DSLR camera so maybe I can get a decent shot when I do. As for black text on a white background and white text on a black background, the Seiki 39" really looks quite good IMO (with sharpness turned down to zero).
I guess basically everything the OP has said here doesn't really apply to me and my Seiki 39" (pending the red text black background test which I don't even necessarily care about for my use case).
For what its worth I don't move my head / neck around in order to take in the screen of the 39" Seiki. Therefore no head or neck discomfort and no eye discomfort either,....