Earlier quoted context omitted.
Some of that info is now considered outdated. In addition there's a lot more benefits your missing. 4K will be streamed at a higher overall bitrate with smaller artifacts and noise. In addition HDR and 10 bit / 4:2:2 or 4:4:4 color can be huge differences in image quality on the right TV and source. For the first example you could theoretically take a 4K signal and downscale to 1080P before display and theoretically…
The bitrate thing is certainly true, but at the bitrates that Netflix streams I'd almost rather have the same bitrate for a 1080P stream and then use my Shield to upscale it. As for the color thing, 4:4:4 has very little material released in that format. And there's a reason we chose to compress 4:2:2 instead of 2:2:4, humans are just much less sensitive to color than to brightness. That's why HDR is so nice, the ext…
Most content that is not 10 bit will also be 4:2:0 - you are right that 4:4:4 is overkill but 4:2:0 does sorta suck.
It's really about the overall the package