I'm a heterosexual man attracted to women.
Giving a man long hair and a skirt doesn't make him a woman and doesn't make him attractive to me. In the same way, a woman having visible muscles, short hair and other stereotypically masculine things doesn't make her a man. These are the things superficial people who can't understand nuances focus on.
It is something in the hormones that changes it for me and I guess most other people, but few have a nuanced enough understanding to comprehend this. When women take male hormones long enough, they start to get masculine face shapes, their voice changes and so on. To me, they are no longer attractive. This has little to do with an ability to beat me up or them being stronger than me.
(Side remark: Superphysiological levels of muscle like roid-taking bodybuilders have never look good.)
Do you understand what I mean?