Honestly speaking, i think 4k resolution is garbage in many ways, first to all, is pointless having such a high resolution in a small screen, like smartphones, portable devices, and 21 inch monitors, there's people out there who can't even distinct 1080p to 720p, i think some companies are interesting in this resolution to represent the "premium" market, being honest at first 1080p was a luxury and now is the norm, so, how does big corporations can keep the interest to the wealthy consumers? adding more of the same, more resolution, more pixel density, etc, and in the meantime, they try to convince the average consumer to get 4k when the technology gets cheaper.
To me 4k is pointless right now, the actual consoles have struggles to get 60 frames per second on 1080P, you need a MONSTROUS BEAST as a PC to gaming in 4k, not to mention 3d artists like me, who can't even render his videos in 4k, dammit!, Source filmmaker can't even render in 1080p, i have to render in 720p and then upscaled to 1080p. and my god!, i can't even imagine the amount of data is gonna required to upload,
my Double Date Orgy video has 10 minutes length. and is rendered in 1080p resolution, the file is 2Gb, i had so much struggles just to upload on the web, imagine with 4k, MI GOD!