Print lighter lines when printing gridlines (Excel for Mac v. 16.37)
I suggest you make the weight of the printed gridlines very light so that they are more comparable to those shown on the worksheet screen. They would then be more like guidelines, and any borderlines included in the worksheet would show. My former 2008 version of Excel for Mac was like I propose.
The current setup prints regular borders around every cell obscuring any regular borders used within the worksheet. I tried using Borders rather than the gridlines, but nothing was as light as the old setup. It would be much easier to have light printed gridlines and use Borders if darker printed gridlines are desired.