The Inventory Report lists all files which has no extension and has dot in the name as the part in the name after the dot is the extension of the file ( for example, test.file2019 is on the Volume, then "file2019" is listed as an extension).
If there are a lot of files like this on the Volume then the report is hardly understandable.

It would be great to list unique file extensions under “(Other Extensions)”, if the files with a unique extension do not use a significant amount of disk space compared to cumulative amount of disk space used by files with a listed common extension.