The whole "but realism" argument falls also flat when considering that there are no real gay Characters, just straights and bisexuals. Might be interpreted as a reflection on the conservative Japanese narrative of Homosexuals as straight-available in denial. (I actually met a Japanese woman who couldn't get her head around the fact that as gay person I won't develop any sexual or romantic feelings for her. In the end I had to finally cut contact after trying to make her see reason multiple times.)
Skyrim is imo a good example for this freedom, NPCs there are either Dohvakiinsexual or not at all, regardless of the Dohvakiin's gender. I think they didn't even have to alternate the dialogues.
Yikes, I've been told the same and it is tbh utterly frustrating. To put it in the words of MLK Jr.:
Of course MLK had bigger issues to fight for, but I think it's fitting regardless.