This has Media indicated in 2 ways in the Charts category’s Pedigee view mode:
In the View → Configure…, the layout tab, the checkbox options to Show images and Show tags have both be selected.
In Person view, use Edit → Tag → Organize Tags… to add a Tag (called Media and colored Gold) and move Up to the top of the Tag list

Created a “Has Media” Custom Rule to look for People with at least 1 media object:
Used the Add/Remove Tags… addon tool to tag People who match the “Has Media” rule with a “Media” tag. Which results in a Pedigree view for the Example.gramps sample tree. (Added a Media object to the Home Person’s maternal grandmother. Just so it represents a case where the box is too small for the Media preview.)

