It's largely because chess has historically been a boys-club type activity. Women were actively discouraged, if not barred, from playing on grounds of misogyny. So, even today, there's very little women taking it seriously.
Of course, we all know there's no difference in the level of intellect or strategy between men and women.
> Of course, we all know there's no difference in the level of intellect or strategy between men and women.
Do we?
I thought it was commonly accepted that the average and median are the same but that men have more outliers on both sides.
That’s the greater variability theory. The male median is also higher so when you combine the two the long tail to the right will be dominated by males, so will the long tail on the left but to a lesser extent.
Many IQ tests have been designed to minimize the difference between males and females, primarily by reducing g-loading. Males pull ahead after puberty, prior to this they have an IQ disadvantage. So you have to take these factors into account when trying to make a fair and proper assessment.