It makes it look like there’s something funny or wrong with a woman’s face looking male to a lesser or bigger extent. Ridiculing a cis person for looking a bit like the opposite sex causes people to ridicule trans people as well. I don’t like the joke because it makes my life more dangerous. It steers the society in a direction that increases my risk to be beaten up or murdered. And yes, here the joke is about unambiguity regarding what the gender of the person is. If there was a joke where the funny part is that someone is wearing a wig (here the wig is a tool for reaching the “funny” look, not the funny thing as for itself), then it would indeed endanger the well-being of every person wearing a wig. This joke here does nothing to ridicule the concept of wearing a wig. But it does ridicule the concept of a woman looking male. It’s saying “this person looks trans. How funny!” I look trans. Why is it funny to you that I look trans?