True, but that's not a gender issue per se. Women-only programming groups are based on the theory that women are not being well served by co-ed programming groups, as a combination of socially enforced gender roles plus an understandable discomfort at being the only woman in a room. All male groups are generally frowned upon because there's no reason to think the average male would be prevented from participating in a technically co-ed but heavily male group.

I suspect men-only clubs for traditionally female dominated fields, something like an all male kindergarten teacher group, would be broadly accepted as reasonable.