Are you sure you successfully reset your preferences?
I can't tell from your screen grab, but you have to have media placed (video or audio). Then the panel will "light up."
Diane, that was my first thought until I saw the screen shot. That panel totally empty, not dimmed.
Missing elements in Panels and other interface issues can usually be restored by deleting your InDesign cache files which is not the same as deleting preferences.
To do so:
For Macintosh Users: The User Library folder in which InDesign’s cache files are stored is hidden by default on most Macintoshes. To access it make sure that InDesign is closed and click on the desktop to launch a Finder Window (Command-N). With this window in column view follow the path User>Home folder (it’s the folder with an icon that looks like a house—it may have the user’s name rather than “Home”) and click on the Home folder. With the Option Key pressed choose Library from the Finder Go Menu. “Library” will now appear within the Home folder. Within the Library folder find the “Caches” folder. Within the Caches folder find and delete the entire folder “Adobe InDesign”. I find that deleting the InDesign cache folder completely leads to a lasting change.
For Windows Users: On Windows 7 and above the caches files are hidden. To find them go to the Control Panel and open Folder Options and then click the View tab. Then select “Show hidden files and folders” or “Show hidden files, folders or drive options” in Advanced Settings. Then delete (or rename) the folder at the end of this path: C:\Users\[User Name]\AppData\Local\Adobe\InDesign\Version [#]\<Language>\Cache.
when with InDesign 2021 and you want to reset preferences, first do a backup of the corresponding Version 16.0 folder.
To access the folder:
Backup the Version 16.0 folder.
Remove the Version 16.0 folder.
InDesign will build the folder from scratch.
You may want to do this also with the Version 16.0 folder of the InDesign cache.
( ACP )