Deleted files still remain in iOS System Data

I just realised that deleting videos does not truly deletes it. It still takes up space in under “System Data”.

Deleting the app, offloading it doesn’t work. Restarting the phone doesn’t seem to work either. Have some screenshot on my phone (iPhone 12 pro)

Only way is to restore from a backup from my experience. Done this whole process 2x and have the same issue. Seems very replicable to me.