Very important side note to TV owners with HDMI 2.1.
Specifically LG TV owners.
If your 'Colour format' shows up as RGB like in your settings, here, it means that the PS5 is not doing any chroma subsampling. Meaning, it is outputting at the full 4:4:4 chroma.
The thing is, the LG TV
will change all the inputs to output your content as 4:2:2 chroma subsampling. Even using Game Mode won't help.
The only way to get full 4:4:4 chroma is to change your PS5's input to 'PC' in the Input Settings on your LG TV. And then use Game Mode in that 'PC input' of cos; because there's no ALLM.
This is very important if you want to fully utilize the full 4:4:4 chroma. Both RGB and YUV444 outputs the full 4:4:4 chroma. This means that every single pixel will get its own colour information.
While in 4:2:2 chroma subsampling, in every 8 pixel, only 4 pixels have accurate colours while the other 4 is sharing the same colour as the 4 accurate ones but with varying levels of brightness. So the result is, less accurate colours for your games that can output the full 4:4:4 chroma.
This has been tested by other LG TV owners in the international AV forums including me where with the RTX 3000 series, even if your PC settings shows you are outputting the full 4:4:4 chroma, the TV is still chroma subsampling the output image. With the solution being to change your input to PC Input.