There is no trans woman in this case. A female boxer, born and raised as a woman, is being attacked and called a man. What OP is saying is that it’s basically because they don’t see her as attractive, and that’s definitely a major component of it.
What it comes down to is that they’re so obsessed with the idea of trans women that they start seeing them everywhere, and it usually comes down to someone not being quite feminine enough in some way, though there have been cases of people trying to claim some of the most conventionally attractive women in the world were secretly trans.