For any APub document created or added to this forum I can select View > Studio > Fields and click on Document Information to reveal the users full name (Author Field)
I can also reveal my own full name the same way, in my local APub files.
I am on Widows and presume this is being picked up in my Windows settings somewhere by Affinity Publisher (not sure what happens on a Mac)
I have been informed I can change this on a per document setting if I remember to change it in the View > Studio > Fields screen on an existing document but new documents etc will always show my full real name.
I request that there is an option to enable/disable this in preferences or to leave the Authors name blank in any new document I create unless I specifically add it.