If you’ve tried everything and it’s still washed out, your display might not have true HDR (e.g., HDR400 with poor local dimming). In that case, disable HDR in-game and stick to SDR – it will look better.
There are several reasons why Hitman 3 HDR may appear washed out on PC: hitman 3 hdr washed out pc better
This yields a 30% improvement in black depth, but still inferior to Special K. If you’ve tried everything and it’s still washed
Some players have reported that switching to a different HDR format can resolve the issue: hitman 3 hdr washed out pc better