Well, back then grammatical genders had not been conflated with sexual genders. It was, pardon the language, inconceivable, that they would be conflated. Lots of languages have gendered nouns and some have gendered verbs.
Nouns aren't actually grammatically gendered in Esperanto. But when a noun refers to something that can physically have gender, male is the root or default.
Esperanto was invented by a single individual who spoke several languages but who didn't have formal training in linguistics.
It basically started off as a pet project of a young (teenage) language enthusiast, so I wouldn't scrutinize his decisions too carefully or expect every decision he made to be optimal.
Or every decision made back then to conform to today's societal values. no language will ever meet that bar. instead of allowing this natural evolution, seems Google (and let's say 10 people at Google) seem to have decided to be the arbiters of linguistic integrity.
