Not really the main point of my comment, but okay.
Firstly, mapping symbols to sound is arbitrary and based on convention.
I don't speak French, but I wouldn't say français.e.s is that much worse than français(e)s, pronunciation-wise. But I do agree that -.e.s is a bit odd. Kinda like w/ and w/o in English. I mean, seriously, why isn't it w. and w.o. like any other abbreviation.