@Ana , In fact, the setting in the baselines default configuration is recommended by the relevant security team.
For the setting "Block game DVR (desktop only)", it specifies whether DVR and broadcasting are allowed.
The Microsoft Game Development Kit (GDK) includes a set of APIs for broadcast notifications that show broadcasting UI, adding metadata to screenshots, video clips, broadcast, and capturing diagnostic screenshots and video.
Based on my researching, sometimes it may capture some unwanted screenshots which may cause risk. I think this maybe the reason to disable it by default. If you want to know more about the setting. You can open a new thread and add "windowa-10 security" tag to see if you can get more help.
Hope the above information can help.
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