I have been researching HDR and comparing it to Windows for quite some time now, and the consensus is that KDE does HDR tone-mapping on games/content that doesn’t support native HDR to some extent, but it does not offer the same visuals as something more advanced like Windows Auto HDR or RTX HDR. This is the only thing keeping me on Windows, as I have a HDR10 capable OLED monitor and the HDR features on Windows make older games without native HDR capabilities look much better.