I have begun a cleanup of a legacy Confluence installation. I am currently focused on the contents of the 'nonspaced' folder in the attachments directory. I have successfully followed the instructions of this article and this article to find and remove draft content belonging to inactive users or more than 1000 days old. Everything is working as expected.
However, I have found about 1250 folders (some containing gigabytes of data) that do not have an entry in the content table. Nor are they referenced in any of the tables that reference contentid.
Can I simply delete these folders?