Without delving into the question of how Gerudo gender roles work, there are two obvious senses in which Ganon can in fact be said to have girl power:
The Triforce is empowered by a trio of goddesses; all Triforce wielders thus wield girl power.
In those instalments in which Ganon has lost or not yet obtained the Triforce, or in which the Triforce is not mentioned, much of his sorcerous potency derives from encasing maidens in giant crystals, stealing magic from otherworldly queens and/or demi-goddesses, enslaving Great Fairies, bodily possessing various princesses in spirit form, etc.; that is, Ganon utilises girl power in the sense that his magic is actually, literally powered by girls.
