If we're going to be pedantic it's not Windows that has directories, it's the file system ==>>
Directory Management - Win32 apps | Microsoft Learn
I use the word 'folder' when I'm communicating in the context of Windows, and 'directory' when I'm communicating in the context of a file System, e.g. NTFS, HPFS, APFS etc.
When we got our copy of version 2.1 of Windows in May 1988, one of the first things we noticed was that "Windows Explorer" used what was by then a 10+ year old de-facto standard 'folder icon' to
represent directories on local DOS disks. We'd seen this on Star, and the Apple Lisa we had in our lab.
Factlet: we weren't allowed to have a Star due to US export restrictions, hence the Lisa. This was in the UK, our joke was: "They'll let you have their nukes but not their boat-anchors."
BR