That's all and well for the women who self-select to perform at ability, but I would argue it's irrelevant to 5 year old girls looking for a fun outlet for their sharp minds. If the proximal rewards for chess are minimal--a boys' club, teaching skewed to the male mind--girls won't persist in chess, no matter how lucrative professional purses might be. It's the same argument as we see for STEM underrepresentation among females.
To me, that there are separate competitons for women suggests attempts are being made to correct for historical underrepresentation of females in chess and change social expectations in the game and elicit higher female participation rates among junior female chess players.
What does the Markov transition matrix look like between beginner and advanced players of similar ability (not outcome) across genders and ages, though? Are females converting from junior to senior levels at similar or higher rates than males, but with a smaller starting population? Or, is there good gender balance at low levels with an age-linked inflection point where gender balance is skewed for similar ability players? The answers to these questions matter because the get at the underlying causes of the imbalance.
I don't think women's vs men's tennis is an appropriate analogy. There is a very real physical difference re: strength, reach, and speed for men in population averages that drives different outcomes. I'd say a more analogous case is underrepresentation of females in C-suite offices which, like female underrepresentation in chess, is driven by myriad factors beyond raw ability.
