Hi! This is a super important feature that I have no idea why is not implemented, but anyway here is an experimental PR for it: Wayland color management by yikerman · Pull Request #22491 · darktable-org/darktable · GitHub.
It utilizes Wayland Color management and HDR protocol (has been available since Feb 2025) and renders image preview in Rec.2020. The compositor is supposed to read display icc profiles and do rest of the transformation works. Currently it works on my PC TM but due to the nature of the development process, more tests are appreciated!