Apple’s attitude to document metadata remains ambivalent. But macOS does offer good support for extended attributes to pass through iCloud, if you know how to access it.
RTFD
How to convert the text content of text, HTML, RTF, Word .doc and .docx, Webarchive, and other files, for free, using a simple command tool.
One of the Finder’s grand illusions, these are standard documents actually composed of a hierarchy of files and folders. Here are some details of common packages.
The Eclectic Light Company 