Assets can be Enabled or Disabled from the Asset Library. This action replaces the previous ‘Delete’ button from the Media Detail. Each Asset has an Enabled/Disabled action. If Disabled, that Asset will cease to play wherever that Asset is being used. This also removes the Asset from any Playlists.
From the Asset Library, click on the Asset to open the Media Detail page and click ‘Disable’:
You can view disabled Assets by toggling between Enabled/Disabled from the top of the Asset Library. Enabling Assets will add them back to the ‘Enabled’ view: