I would be curious to hear the viewpoint of anyone who used a mask solo. I assume this was a rental situation and you didn't want to get spittle and sneezix on the instruments or something?
I puzzle at solo drivers that I see wearing masks also. I feel way out of the loop on why that makes sense. I see the drivers with masks very often. (5% of drivers around here maybe?)
(I'm in the majority of "no masks" myself, have flown numerous times with CFIs, non-family non-pilots, and family/friends during this)