[the8472]

> and lots of video compression algorithms will turn smooth gradients into blocky messes that would benefit from dithering.

More accurately: Either you have a 10bit-per-channel video (or better) which has smooth gradients which will need dithering when rendering to an 8bit-per-channel display.

Or you have 8bit video (more common) which will have to be passed through a debanding filter first. But then how do you get the debanded result onto the screen without reintroducing the banding? By dithering it.