There’s a couple of potential reasons I could come up with.
One would be - sex development in the womb is not even, in the sense that it’s not the case that the child starts out following either male or female development patterns. What happens is that the fetus starts out following female development patterns, and then the presence of androgenic hormones changes the development to male. If gender dysphoria is caused by issues with the development of the brain not matching the chromosomal and external sex characteristics, it would be unsurprising that it might not come out evenly.
Another thought is that it’s far, far more acceptable in Western society to be a masculine female than to be a feminine male. So for women with more masculine traits, it’s easier to live in a way that’s acceptable to society, than it is for a feminine man. So the latter may be more likely to seek to transition in search of acceptability.