There is macOS file system metadata, and then there is PDF metadata. The PDF file format itself contains metadata for the Title, Creator, Author, encoding software used, creation Date and more. This is separate from the data that macOS can append to a file on its disks.

Various third-party apps, like Acrobat, PDFPen Pro, etc, provide dialogs to edit this data. You can also modify it with Automator.

You'd need to create a workflow that takes a PDF as input, and then changes the metadata to something else, which could be " ".

Note that you can't change the Encoding Software value.

There is macOS file system metadata, and then there is PDF metadata. The PDF file format itself contains metadata for the Title, Creator, Author, encoding software used, creation Date and more. This is separate from the data that macOS can append to a file on its disks.

Various third-party apps, like Acrobat, PDFPen Pro, etc, provide dialogs to edit this data. You can also modify it with Automator.

You'd need to create a workflow that takes a PDF as input, and then changes the metadata to something else, which could be " ".

Note that it doesn't contain 'your OS', but the version of MacOS that made the PDF.

Note that you can't change the Encoding Software value.