Tagging folders

I could swear that I used to be able to include a tag with a folder (using "get info) and all documents in that folder and all sub-folders would inherit that tag.

I tried this today and it no longer works that way. Am I missing something?

When I decided to check on “Preference/General” I saw “unify tags”, what does this mean?

Thanks in advance.

This can be enabled in File > Database Properties.

From the Help > Documentation > Preferences > General

which links to Windows > Sidebar: Navigate > Unified Items