Re 8K.
I noticed today that Samsung 65" 8K TVs are now AU$6k, which is only AU$1,700 more than the Samsung 55" 4k i bought a few years ago.
That 65" 8k has just a bit more than the area of two 43"4ks, but with twice the pixels. Of course, at native resolution, that is small text, so scaling to 150% in Windows would make it effectively the same pixels as the 2 4ks, but with much better-rendered smooth-outlined text than tiny pixelated natural.
The main problem with using 8k TVs on a computer is getting a video card that can handle 8k HDMI. There are cards that can handle DisplayPort 8k monitors, such as those based upon the GTX 1080.