This is a change made to Word's "text rendering engine" in Word 2013. It seems we are stuck with it. If you do not need the features added with Word 2013 and 2016, if you have your documents in compatibility mode for Word 2010 you will see the text boundaries you are used to.
See the download samples "Text Boundaries Template for Word 2013/2016/365" on my downloads page.
Downloads - Microsoft Word - Add-Ins - Tutorials - Letterhead - Templates
For more information on this, see
Text Boundaries Display in Microsoft Word.