Hmm, I'd argue that without the facts there isn't a logical line to draw here though.

Without being clear that biological sex is the issue and defining *why* it's an issue, you're stuck with a long, imprecise, metaphyscial argument about what it means to be a woman. Trans women on hormones are biologically different to males as well. But many people thing that a drop in testosterone levels the playing field. You need facts to demonstrate that it doesn't.

The most common counter argument to the case I make for sports is that there are differences in athletic prowess WITHIN the sexes. And it's true. It's argubly far more unfair that Ronda Rousey competes against women that it would be if I did. I'm sure she's stronger than me in every way.

And some people DO make the argument for getting rid of sex segregation in sports and just having everybody compete with each other. As far as I can see, it's only the range of advantage that males have over females that makes the argument against trans women in sport compelling.