Same here , I play on a sony 4k hdtv and with vulkan is blurry and washed out, switching do dx11 solved it but I'd like to try new api too, but this kind of configuration (pc--->4k tv) has some sort of bugs ???

There is a workaround, open to c:\SteamLibrary\steamapps\common\Baldurs Gate 3\bin and edit the property of bg3.exe (under compatibility tab select change "high DPI settings", check "High DPI scaling override Scaling performed by" Application. Doing this the game's graphic is crisp but I hope for an ufficial solution.