"Yes, I know they were playing fortnight, that was kind of the point of my comment."
Then I don't understand your point about how you think it's nothing to do with socialisation, and instead somehow being that girls are apparently not as competitive for boys in context of Fortnight being an inherently competitive game played in a literal competition.
I don't believe you really think that women only competitions are a thing just because women "prefer" them that way.
You have already had it explained to you why there are women's single sex competitions for things like gaming and pool, including how males have faster responses and the controllers being made for man sized hands.
So, I think ignoring all of that and coming back with "well if it's just because you prefer it that way, don't complain when sexist men jump on this as an excuse to exclude women for no reason at all" is just childish.
FWIW, in case you weren't aware, men do have lots of groups, clubs and competitions (may I direct your attention to most sports) etc that are single sex already, so that's good news isn't it?
I've yet to hear of a woman complain about the men's sheds initiative for example, in fact I and the other women I've heard speak about it are all for groups like that. There is a clear difference between misogyny and needful single sex groups, clubs, competitions, support groups for both sexes. I don't think it's too hard to tell the difference between the two personally.