From Sebastian Wick’s Mastodon
Blender is getting HDR on Linux via Wayland before Windows! This isn’t by accident, but shows how creating a system with a different design creates better results for users and application developers.
Firefox is in this same boat too. It will get HDR support on Linux* sooner than Windows. Firefox currently only supports HDR on MacOS.
Tldr: linux now handles hdr better than windows, and as a result blender us supporting hdr on linux, but not on windows.