You need to buy a large screen 4K flat screen to start. And then you can tell looking at the images like the blades of grass, leaves edges, and faces. The details are not there in broadcast OTA.
Yes, I was wrong about resolution. Now that I have slept on it, I remember video cards adding more colors at certain resolutions looking better. But it is the resolution that defines the edges of details.
Take your large 4K TV. Watch a 4K blu ray on it, something with good detail and lots of motion.
Now watch the same thing via 4K streaming.
Until you do that, stop making foolish statements or comparing apples to oranges.
I promise you, it will be an eye-opening experience.
As far as OTA if you don't have any stations broadcasting 4K (fairly rare) then can't really put that in the mix. But you might actually find a 1080 OTA in some cases will be better than a 4K stream, especially for motion/action/sports which is where the compression becomes very evident.
Resolution is one piece of the puzzle, and can be very misleading. I can broadcast a 4K uncompressed screen that is actually a 360i image at the source. As long as the output on your end has 3840x2160 pixels, it is 4k, and will look very blotchy and crappy.
Color depth is one of the first things to go as that takes a ton of bandwidth.
Next the remaining data is encoded and what it sees as "unnecessary" information is lost. Of course that information is necessary, but they figure the average person won't notice.
One of the main things they do when encoding and compressing is remove some of those 8.2 million pixels that makes up the 4K image and let the decoder "fill them back in" at the other end, using guesswork as to what should be there.
Really bad compression/encoding techniques (mostly older but still in use in some cases, especially the "on the fly" version when it detects you don't have enough bandwidth) simply takes 4, 8, 16, pixels and combines them into one single big dot. That when things get really blurry and blotchy. Even if only 4 pixels, it basically turns your 4k into 720, even though your TV will report 4k resolution.
Compression and encoding often do not handle fast motion well, giving you squares and blocks, because it can't figure out what to fill in the blanks with, since the surrounding pixels are changing so quickly.
Upscaling does the same thing, fill in the missing info, it usually does not work very well. Faroudja and a few others did it quite well back in the days when 480P came along, but that was going from 360 to 480, not a big leap. At these higher resolutions, unless you invest in a super high end AV receiver or blu ray player, upscaling is a bit of a joke. I guarantee your streaming stick isn't doing it well.
That's a brief education on the parts you're missing, again you can do some research on this stuff, or like I said, the easiest way to prove it is look at uncompressed (or very lightly compressed) like a 4K Blu Ray or even a standard Blu Ray vs streaming and see the clear difference for yourself.
Checking out of this conversation at this point as it just keeps circling back to the same things.
