Or vice versa, etc. with some caveats (see below). As per the Wikipedia article on gender fluidity:
A genderfluid person may fluctuate among different gender expressions over their lifetime, or express multiple aspects of various gender markers simultaneously.
As I understand it, these gender markers might not be the same as sexual characteristics. For example, a person with feminine clothing and a penis could be a trans woman or femboy depending on what traits they consider defining of their gender, and might be intersex or not. Not to mention non-committal states like gender questioning and exploration, or crossdressing for entertainment or a Gerudo Town visit. They can find terms like “nonbinary” and “genderfluid” derogatory, especially if they encompass a trait they are indifferent to, dysphoric or sensitive about.
Am I wrong about something here?
I do differentiate between genderfluid and questioning, and only call the latter “non-committal” (that distinction is made in the next sentence in the Wikipedia article), although I guess mentioning it next to fun crossdressing could play down the exploration process. And I did make the distinction between biological (sexual) characteristics, gender expression and gender identity (which is usually based on some or all gender characteristics).
I suppose I didn’t make myself clear enough: it’s up to people to select their gender identity based on their feeling, and also a separate gender expression (although they tend to correlate), regardless of biological characteristics. What’s new to me is that the “genderfluid” label can refer to gender expression varying across the body, not just in time. Yes, the title is a bit reductive and I guess it might be incorrectly interpreted as one implying the other, hence the explanation (which only lists a couple examples of common identities of feminine-looking people with penises). Not to mention, terms are evolving: “bisexual” used to be a synonym of “hermaphroditic”.
By the way, use the forward slash for an ASCII ≠ (=/=), a single backslash gets hidden by most Markdown interpreters