As it is, MOST newly released UHD 4K releases are upconverted from 2K masters and before I contemplate making a 4K purchase, I always read the reviews @ blu~ray.com to see what the genesis of the master is. And the studios are just beginning to release 4K discs which are worth anything, IMO like Blade Runner, Close Encounters, etc. Finding the 'few' true 4K mastered UHD discs is quite the challenge, at present!
Ironically, even Criterion continues to release ALL of their new 1080p BD~A/DVD [gulp] releases from 4K upconverted masters but have NOT released a single UHD 4K release as of yet.
Perhaps 8K and then 16K can find their fan base with interior designers and Broadway set designers who can create virtual realities in the homes of the very wealthy who want interior changes with the click of a mouse or on a Broadway stage with truer than life set pieces on gigundus flat panels!
As for home video.........you'd probably have to have [at the VERY minimum] 100" or MUCH greater flatscreens to discern the difference between 4K and 8K and hold on to yer britches 16K!
And to think the music industry lags way behind their video counterparts struggling [my word] to release music in 5.1 surround or greater when in most listeners' minds, plain ole low res stereo is more than adequate.