These kind of articles play off of peoples misunderstanding of gender versus sex. Sex is what kind of junk you have. Gender is what kind of objects you like to jam into holes.
Actually, that's sexual preference, not gender. A working definition of "gender", as the left uses that term, is "the characteristics of women, men, girls and boys that are socially constructed. This includes norms, behaviours and roles associated with being a woman, man, girl or boy."
In short, sexual stereotypes. And that's exactly why the team trannies and the "TERFs" (trans-exclusionary radical feminists) are at war.
A core part of early feminism was destroying sexual stereotypes in terms of behavior, dress, interests, etc.. So to one of those feminists, you can still be a woman and dress, act, etc., however you wish. Including in ways that were traditionally considered "masculine.". All those butch lesbians, for example.
The trannies want to stand all that on its head, and basically say that the socially-created stereotypes themselves define whether you are a man or woman. So, those two groups really don't get along. And in this particular instance, I think the radical feminists have it right, and the trannies are wrong.
Gender is a grammatical category. It governs the use of nouns and pronouns in language. There are three genders, at least in English. Why is this so hard for people to understand?