See, I think you’re onto something.
Looking at the results (it’s about 60 votes per choice at the moment), it seems that more voters are open to playing vampires/ghosts/aliens/demons than they are cows/cats/owls, BUT that the voters are more sensitive to gender when it comes to the first group of non-human characters. They don’t care as much about gender when it comes to cats, but gender matters more with aliens and ghosts. Hmmmm…
So perhaps this plays into your view of vampires/ghosts being a bit more “relatable” from our human vantage point, and thus sex/attraction/gender/identity/orientation comes more to the forefront?