If the default folder exclusions of $Recycle.Bin,System Volume information and .snapshot are removed from the content rule,the backup will scan data in these folders as well. Also the folders with name #recycle, #snapshot will also get scanned.

Hence the Data Scan size reported in the UI could be greater than the size of the folder on disk as seen in the folder properties.

Don’t remove the default folder exclusions of $Recycle.Bin,System Volume information and .snapshot from the content rule