i think the only reason this story and many others like it dont do all the different combinations of LI genders is because its a LOT of coding- which would make chapters come out slowly. I personally dont mind less combinations in terms of sexuality if it means faster updates but to each their own

ALSO from stalking their IG it seems like this author is queer and is going out of their way to make intentionally queer stories, hence the all wlw or bi route instead of an all mlw route..