What kind of argument against implementing "they/them" or choosing gender pronouns at character creation is that "Mr. Orc doesn't care, he's gonna eat you anyway"?
Besides, the way the tag system work it would be a breeze to implement (other than the translations). "Female" and "Male" are tags, like "Bard" or "Halfling" and they are what define dialogue options. I bet that this could be solved by an unofficial mod in a jiffy, English is an easy-going gender-neutral language most of the time, and the only time-consuming hurdle would be managing the translations, which is NOT expensive, particularly as the ones available in gendered languages have been crafted with a lot of care and there is software that would help find the variations and implementing them a breeze.
Female and Male are the designations for the two human genotypes. There is no currently genotype or chromosomal combination designated by science to include "straight" "gay" "queer", bi-normal" or such. Those are psychological/emotional/behavioral designations - again, I will not contradict or deny anyone their self-identification. In the US we have a number of folks who have self-identified as black, latinx, native-american and so on, often with not a single hereditary, genetic, ancestral or cultural tie to the self-designation other than "I feel like I belong to that group". This seems to be the newest frontier - I won't gainsay their self-identification - but sometimes a rose is a rose.
However, people base initial identification on observational data. If it looks like a car, absent any data or information to the contrary, it will be called a car. Once it turns into a giant robot, it may be deemed a Transformer, but until then, it's a car.
A rose by any other name is still a rose.
Larian is welcome to create a system such as you request, then welcome to go through each and every conversation and determine in which the npc the character is speaking with will give a damn, and which (said Orc) will not, then create appropriate alternate responses.
Whether this is a productive use of their resources, given the many other issues they need to resolve, and the additional income this might create via additional purchasers of the game is not my decision.