Word for Mac: markup turned on by default

I think your question is about printing comments by default. P rinting of markup has long been the default setting in Word for Windows. I am not on the Mac.

In Word for Windows you can put the Track Changes status on the status bar at the bottom of the Word Window and clicking on that will toggle it.

Once you have tracked changes or comments in a document you can turn off display of them but they are still there. The only way to eliminate ones that are in a document is to accept/reject changes and delete comments. When printing, in Word for Window, markup is printed by default. That can be unchecked but it is not necessarily obvious.

In Word for Windows, you need to click on Print All Pages to even see the Print Markup.

In Word for Windows, the markup is showing in the Print Preview and space for it is reserved on the right even on pages where there is no markup.

Is this all documents or just particular documents?

What is your Word version number?

What is your Operating System Name and number?