As PaMP always needs deployments to start updates, the Discovery > Unmanaged list is some kind of recurring working list.
However, there are always special apps that shall not be handled by any patching process (e.g. development libraries, ...). We want to hide / mute these apps, so that they are not shown on the next review again and do not clutter our somewhat "discoveries-create-deployments-todo-list".
I compare this with "accept risk" for MSFT Defender recommendations.
P.S.: We are aware of the custom script at https://github.com/PatchMyPCTeam/Community-Scripts/blob/main/Other/Reports/Get-PMPCFoundApps.ps1 but this still relies on additional steps / reports to be analyzed and not just using PaMP for the process.