I'm definitely not into people being phobic -- and I did mention phobic, not specifically bigoted against gay guys, or lesbians, or whatever else, in my original post. Mostly I was writing from my own perspective, because that's what I know, and I didn't want to speak for someone with a different experience; but we do, regardless, need more representation, more diversity, and less gatekeeping, less shaming, and less making people scared to even tell a story they want to tell.
I don't think that the subculture, if it can even be called that, encourages misogyny or any other intolerance. Some people will do it, and they'll do that anyway, regardless of what they write. As a fan (ish) of Supernatural, I can also say that the writers of the show are far more guilty of seeming misogyny towards supporting characters than the fandom -- and there's a vast disconnect between the production crew and the fandom -- though I'm not exactly a fan of the fandom either. I just enjoyed the show for a while and moved on with my life. But frankly, when you have gay guys as your main characters, your ideal foil/antagonist/punctuation will be a character different from them that may not understand them. It's not exactly an uncommon experience for gay men to come to a realization they're not straight, and it's very common for their girlfriends or wives to be less than understanding; this can present a deeper, more profound opportunity for development of a character, but that has to be up to the writer. And as for slutty, well...a lot of gay guys like women who are in control of their sexuality and sexual identity. I always liked sluts. Up with sluts! And bitchy? There's an art form to throwing shade. There's a reason why so many of us loved Jessica Lange and Frances Conroy trading barbs on American Horror Story.
And speaking personally, I'd rather not bring "cis" and related into it; that's another issue for another conversation and we're just dividing and subdividing. Keeping it simple enough and straightforward enough, BL and GL is helpful more than it's not, and more times than not is written by people who like it and want to tell their story. Erasure is a popular media problem, but it won't be helped by making people afraid to write more stories.