[p9fus]

You can shorten that to oklch(62.8% 0.2576 29.23) and it will still max out the red subpixel on your sRGB monitor, not that this is a particularly serious flaw with okLCH anyway IMO, especially compared to the incomprehensible nonsense that is #RRGGBB unless you're specifically working with sRGB subpixels/pixels and not colour