HDR is a tacked on feature in KDE that barely works. In Windows 11, it's a set and forget thing. SDR gets mapped to HDR space, so you don't have to constantly toggle it on and off when switching between content, like you have to do in other OSes. You can even upgrade SDR videos and games to true HDR, even if they don't have native support. It legit makes content look more realistic.
And if you have a newer GPU, there's also AI upscaling, which is great for watching HD and SD content on a 4K display. Pretty sure you can't do that* at all in Linux, at least not in real-time.
But if you have an SDR monitor and/or an older GPU, none of this matters to you. Which in that case, there's no reason for you to use Windows ever. But if your gear is newer, Linux is too outdated for you.
I'll check back in 5 years. Maybe 2029 will finally be the year I ditch Microsoft products for good.