I mean, in the dark ages, you only hear of people burning witches and not wizards. Why was it widely believed back then that women could be magical but not really men as well?
Many of the accused "witches" were men. This is a question of semantics: people believed that men as well as women could be witches, and practitioners of various "magical" approaches to health and other issues - people who employed the European folk belief system in ways that some might regard as drawing on magic - were both men and women.
"Wizard" is a term that appears more in folk stories than in reality. Merlin was a wizard in stories describing King Arthur, for example, but one would find it difficult to find "Merlin the Wizard" in primary sources dating from the supposed period of Arthur. There were court astrologers and others who toyed with science or pseudoscientific endeavors. These people - often men - might be called wizards by people in retrospect, but I doubt the term was generally applied. Perhaps someone here has an example of the term "wizard" being applied to someone in his lifetime, but I can't think of such a situation.