I don’t see why some people make a big fuss about a guy wearing a skirt or dress!
For centuries even millennia, men have been wearing tunics, skirts, dresses, and some pretty elaborated. Of course, the first example that comes to mind is the Scots and their kilts, but many modern cultures have dresses and skirt-wearing men.
If it is a loose body covering, short, medium, or long, it is a dress, whatever the name you give it. It is a skirt if it is wrapped or attached around your hips and hanging down, covering your legs.
I don’t think it would be a good idea to go shopping at the Marrakech souk wearing a see-through djellaba with just your underwear, but this picture is a Fashion editorial. No offenses intended to my Marocains’ friends. It is mostly the occidental society that has created this men and skirt dress taboo. For the rest of the planet, wearing a djellaba, a tunic, a kilt, or a loincloth is no better or worse than wearing jeans.