Gray listed items are specifically mentioned in this document:
About iCloud Music Library icons and status - Apple Support
If your songs appear in light gray text
Your songs might appear in iTunes in light gray text for a variety of reasons. Those reasons include:
- You're not connected to iCloud Music Library. If you see a Disconnected icon in the upper-right corner of iTunes, you're not connected to iCloud Music Library. Click the icon to reconnect.
- The song isn't in Apple Music or isn't available in your current country or region. These songs also appear in gray if you search for them in Apple Music.
- Restrictions are turned on for explicit tracks. Learn more about Restrictions.
- An artist or content provider made changes or edits to an album. You might need to remove the album from your libraryand add it back from the Apple Music catalog.
If the 4th bullet point applies, then you will have to add those again. You can do that by album instead of by song, if that matches your situation.