agreed that it’s disrespectful and morally wrong to push a gender narrative on someone but I raise you this: it’s also disrespectful and morally wrong to push a sexuality narrative onto someone, especially someone who has made it quite clear they want their sexuality to remain unlabeled. which is something this side of the fandom does so fucking often, pushing labels onto harry and also completely disregarding a potential attraction to women etc which is just as bad as insisting hes straight imo
From your raise I raise you this: I, like many from the scientific women, sexuality, and gender studies side of academia, use "bi" as an umbrella term, which can encompass all non-straight and non-gay identities, including fluidity.
Calling out blatant bi (again using this as an umbrella term) phobia is not at all morally equivalent to assigning gender onto another person. Assigning a gender on a person is not acceptable in any situation.
Disregarding harrys attraction to women is bi*phobia. Harry has made it clear that he is not straight nor gay, but that its "not important" which would allow him to fall under the unlabeled bi umbrella.
Here's a peer reviewed study on unlabeled bi identities.
And from personal experience: I studied gender and sexuality studies in college and also identify as unlabeled similar to harry.