Idk why everyone is talking about gender segregation in chess today (and I don't care, so don't answer), but it's interesting to see the discussion veering accidentally close to the real question, which is "why is any competition gender segregated?" Is it 1) because men are obviously superior to women so it would be unfair to women to make them compete with men? Or maybe it's 2) the patriarchy dictates that a man must never have to lose to a woman. It's a mystery.