The XBOX Series X/S will output the Menu in SDR. You can set it to allow HDR10 for content that supports it. You can set SDR games for Auto HDR to convert them to HDR10 for output. You can set it to allow Dolby Vision for Videos and also for Games. Only those videos and games that support it will be output in Dolby Vision. Otherwise, they will be output in SDR. They will output in HDR10 if they support it or if Auto HDR is enabled. You can set the display to HGIG when outputting in HDR10 so only the XBOX handles the tone mapping or use the display's tone mapping feature on top of it. Tone mapping will not be selectable in the display when outputting in Dolby Vision.
Forgot, while the XBOX Series X supports Dolby Vision for streaming content and games, it does not support Dolby Vision for UHD disc playback. Stupid.