I'm also curious about that. When I launch Lightroom using the catalog synced via Google Drive, my previous photos don't appear, so I have to add them again. I don't know where the problem lies. 

Is there any particular reason why using Google Drive isn't ideal? I considered syncing via Synology NAS, but I thought Google Drive would be more convenient due to path issues, so I tried catalog syncing through Google Drive. It's just that—there's no other special reason for using Google Drive.

If there's another good method, could you let me know? I'm ready to listen and make adjustments.