So you see it as a good thing to get rid of the "wrong people" from what is already a niche hobby? "We're driving 'those people' out, so buy our products" is a selling point?
Having seen what happens to MMO populations when the developers decide not to get rid of the "wrong people": Yes, it absolutely is. If you don't do anything to suggest that the trolls should go elsewhere, they will drive away a lot of other people and make the environment unpleasant for lots of people.
There's a pretty long history of gaming groups being seriously unwelcoming to, say, women. However, that wasn't the majority of players being unwelcoming; it was a small minority, plus lots of people feeling like they couldn't do anything about it. When we started driving away that tiny population of people who were overtly hostile to women, we started getting more women at the table... And the hobby
grew as a result.
Bigots are bad for the hobby.
And I am the type of GM who would ban bisexual characters unless there is a VERY good explanation why I shouldn't. This is because I have never seen an example of bisexuality or homosexuality in PCs that was not either A) trying to be stereotypically homosexual for the shock value, or B) trying to make a real-world political/moral statement.
And how exactly do you define "trying to make a real-world political/moral statement"? What makes one character's sexuality a "real-world political/moral statement", and another's not? I've seen at least a few bi characters in D&D games, and I've never thought much of it, because there was nothing particularly political about it; they were just characters acting the way they would.
I also generally ban transsexuality because in a world full of magic, it doesn't make sense; think your body is the wrong gender? Get magic to fix it. Problem solved.
First off, what magic, exactly? What magic
available to first level characters, specifically? Because this doesn't seem at all consistent with the world. That's like saying there's no reason for there to be any people in the game world with wooden legs, because after all, magic could fix that. Or any orphans. Parents dead? Get magic to fix it. Problem solved.
Wasn't planning on defending it, but since you can't wait for me to do so, I will. Moral and religious disapproval of homosexuality, transsexuality, and really, most other things, is not bigotry; it is disapproval. Bigotry is declaring that a person has no value and should be driven out of a city, job, or the role playing community. Believe it or not, not everybody who says homosexuality is wrong is acting out of hate. Most aren't.
I've met one person so far that I think could credibly claim to be expressing disapproval but not bigotry. Maybe two. I've met hundreds who claim they are not bigoted, but whose behavior and actions show a consistent bias towards denying other people their humanity.
Furthermore, it's not necessarily "bigotry" to claim that people ought to be excluded from a community; it depends on
why you want them excluded. Harm to the community is a good reason. Being someone you personally don't like isn't.
Further, transsexuality is, ultimately, a religious claim; it is based on the gnostic assertion that the mind and spirit are superior to the physical world, and that the physical world is wrong when they are in conflict. I do not believe that, and I will not act as though I do.
This is complete nonsense. You're about 40 years out of date on research; at this point, we have a pretty good idea how sexual dimorphism works in humans, and this has nothing to do with some kind of strange gnostic assertion, and a whole lot to do with how mammalian instincts operate.
The role-playing community is full of people of many different views on many different things. To declare openly that you support changing the demographics so that only "the right people" play in the hobby, as the actual bigotry.
No, it's not, because "the right people" doesn't mean "the people who share a particular set of views" but "the people who are willing to let other people play the characters they want". No one cares how you personally feel about the hypothetical moral questions, just how you treat the other players. Nothing in the rules demands that you believe that homosexuality is morally acceptable in our world, after all.