I always assumed that for streaming sites bitrate was a bigger factor

iso1631 · on March 18, 2022

Of course it is, a 1080p video at 10mbit will almost always look better than a 4k video at 1mbit, and a 4k video at 10mbit will almost always look better than a 1080p video at 1mbit.

The far more interesting question is if you accept you have Xmbit to play with, what is better on a given platform (screen size, resolution, viewing situation, how well compression works, how much battery is used in decoding, etc)

brigade · on March 18, 2022

And bitrate goes up for 4k tiers. Even if bitrate only doubles for 4x the amount of pixels, that'll probably look better with modern codecs (depending on where in the quantization curve you are), and most services use at least 3x the bitrate for 4k over 2k, across the same codec.