L'Académie has done this in the past, and is dealing with the blowback today.
French, as people tend to know, uses gender in its grammar. Originally, there were feminine forms such as philosophesse in widespread use, but in the 1600s, around the time L'Académie was founded, the idea that "the masculine prevails over the feminine" became a standard French published grammars and dictionaries used, and they explicitly declared this to be the case not because it was an existing linguistic rule in French but because the language should reflect the "natural" male-dominant society of the time. So words such as la philosophesse was declared grammatically incorrect: le philosophe was the only proper term. (Besides, they probably chuckled, it's not like the little ladies could really think anyway, amirite?)
No really, they said that. And L'Académie, who still don't like girl cooties, was on board and kept enforcing that. So you'd see situations where, for instance, if you had an symphony orchestra of entirely female musicians, they'd be referred to as les musiciennes (fem.pl). If they added a single man to the orchestra, now the group is les musiciens (masc.pl), even though the man is outnumbered 100:1.
The blowback happening now, which les immortels (of course, never les immortelles) are fighting hard against, is to tweak French to be a bit more inclusive, by doing things like creating constructions analogous to the "Latinx" term, changing some nouns so that the feminine form is fully accepted as grammatically equal to the male, and perhaps even considered the default; to use an example I just made up, if you referred "an engineer" as a generic, you'd use une ingénieure instead of un ingénieur. And even stopping that stupidity where a single man changes the entire grammatical gender of a group, regardless of how outnumbered he is.