The objects referred to by nouns aren't inherently gendered, gender is a feature of grammar (sex is a feature of some classes of objects, and fairly recently the grammatical term was adopted as a euphemism for sex by people afraid of the word "sex", and even more recently, inspired by that use, as a name of a social construct associated with, but distinct from, biological sex.)
But grammatical genders, while in some languages they have some correlation to sex distinctions, have no necessary relation to them, as gender distinctions may be on other axes entirely.
So the whole statement seems based on not understanding what "gender" is at all.
Your parent was just saying gender is unnecessary, and you did not answer anything to disprove that, or to prove that they were once needed.
For instance (speaking of Latin), why is Lapis (stone) masculine but Saxum (stone) neuter?
The Romans could have chosen to place all new words on the 2nd declension neuter (the simplest) but instead it (Classical Latin) created 3 more 3rd declension variants on top of the existing ones! And it was more productive, in this 3rd declension, in assigning masculine and feminine rather than neutral, which the 3rd declension also supported!
So what is the reason for that?
Gender isn't senseless, it's a checksum strategy for information. It's not even about sex, lots of grammars have genders that have nothing to do with male/female. The point of gender is agreement: if you're talking about something female, all verbs, adjectives, and adverbs in the sentence have to agree, or the listener gets a syntax error. The syntax error helps the listener figure out that they missed something, or that the transmission was garbled. https://www.reddit.com/r/linguistics/comments/3i1695/eli5_wh...
If you get rid of gender, as English mostly has, you end up forced to adopt different constraints that seem equally arbitrary and wasteful, like strict word order and lots of prepositions. https://www.reddit.com/r/linguistics/comments/3i1695/eli5_wh...
Very excellent comment demonstrating the point about English and word order - in Russian, you can say three words that mean "the dog saw the rabbit" in every possible order, and it's still a valid sentence that means the same thing, because Russian doesn't depend on word order. If it was English, "the dog saw the rabbit", "saw the rabbit the dog", "saw the dog the rabbit", "the rabbit the dog saw", and "the dog the rabbit saw" would all mean exactly the same thing, unambiguously, because the gender of "dog" would have to match the gender of "saw". https://www.reddit.com/r/linguistics/comments/1kdxsc/are_the...
Languages aren't generally products of design.
