I disagree with everyone saying, "Why create something separate for women? Isn't that further separation?" For the most part, women don't take up much space in the tech industry. Women look at the big names in tech, and they don't really see people who are "like me." This can be intimidating and disheartening. Creating more spaces for women to connect with other women, and share their experiences and encouragement is…
> Also, there's no reason why any women's group should have to admit men to appease the "I promise we're not sexist against men" line of reasoning. Is sexism not reason enough in itself? Is this not the very thing we're trying to fight against? I fully acknowledge and lament that there is a severe lack of women in tech, and were it up to me men and women both would have equal opportunities in all regards, but you onl…
Most don't fully exclude men, but they have legitimate reasons to want to make it feel like a female space, and if that means taking measures that prevent some men who would like to attend from attending, that's not necessarily a problem.
I say this as a male who has attended campus women in CS dinners and talks. These events are open to all, but aimed at giving women interested in computer science a community, role models, etc. When I go, I am always prepared to leave if I feel that my presence is hurting the overall atmosphere, because I realize that the events are a powerful force against inequalities in society, and the least I can do is stay out of the way. And when you ask the organizers if men can come, they say yes, but they do mention that it's important for it to feel like a female space, and that if it got to the point that so many men attended that this compromised that feeling, they would start discouraging men from attending.
Not every event needs to serve everyone in the industry. There are probably some language-focused meetups where you wouldn't feel especially comfortable or welcome because you don't know the language, or maybe even actively hate it. I understand that you feel it is different because you'd at least be allowed to attend a meetup for a language you don't know, but it still illustrates that not all events in the industry have to cater to you. When they're catering toward a disadvantaged group, they deserve even more leeway to make sure they achieve their goals. As long as the network of women-focused events doesn't become so large and meaningful that it is systematically disadvantaging men, I don't see any problem with some events excluding men in various ways.
You're concerned about sexism in the small--in this one event. Others are more concerned with sexism in the large--the pervasive social environment that systematically discourages women from entering an extremely rewarding and lucrative industry. Both are suboptimal. In the ideal world, there wouldn't be any women-only tech events. But in the ideal world, there wouldn't be any cultural problems in the industry that make women feel less welcome and free to speak at an event with significant male attendance than at an event that is all or nearly all women. Understand that if organizers choose to, say, split the tickets so that at most 25% of tickets may go to men, they're not doing it because they want to discriminate against men, but because they worry that allowing too many men to attend will make their event less effective at correcting an injustice that we all believe is worth fixing.