News flash, people who claim to be excluded want to exclude others. Also, water is wet.

For real though, female in-group preference is a real thing and much higher than male in-group preference. Men actually build open and welcoming groups while women want private girls clubs.

Our ancestors had it right: polite chit chat at the dinner table, then women go finish chores while men head to the drawing room for brandy, cigars, and serious talk.