Look: what your nerves do has absolutely no relation to what your sexual orientation is. It is not like gay and bi men have magic wiring that makes anal sex pleasurable for them and not for straight men. Cis dudes all have the same bits! There was a similar fight back in the days of the Lesbian Sex Wars, when a bunch of people decided that lesbians shouldn’t penetrate each other because it’s phallocentric and male-defined sex. (Even though lesbians can have penises, but as a rule those people didn’t like trans people very much either.) But the thing is that you can be a totally liberated woman-identified woman and still enjoy having something inside your vagina when you’re horny. Just like you can be the straightest straight dude that ever straighted and still want to have something in your ass when you’re turned on.