steps:

1. on Windows machine with Nvidia card
2. in Windows Display Settings, enable HDR for the display and set it as the main display
3. open attached project "HDR-1.zip"
3. make sure editor is using Vulkan
4. open "test" scene
5. hit play
6. on GameView, observe the spectrum color looks clamped.
    on the on-screen GUI observe that HDR is active and available,
    but graphicsFormat is None,
    and displayColorGamut is sRGB which indicates that output content is not HDR

see attached screenshot (image (52).png)

reproducible:
2023.3.0a9
2022.3.10f1
with Win10 Nvidia RTX3080 laptop GPU - Vulkan editor and player

not reprodubile:
2023.3.0a7
2022.3.10f1
with AMD Radeon 6800M - Win Vulkan editor