None of them would be comfortable joining an organization that was about excluding others based on their demographics (e.g., race, gender, orientation, etc.). That's one of the reasons I hold them in high regard.
If women felt liked they belonged in this industry, they wouldn’t form groups like this at all. Furthermore, don’t strawman them by saying you wouldn’t associate with those who would exclude based on gender, ethnicity, etc. The article clearly states that this is a place for women to seek advice and mentorship from one another. Please don’t bring any other factors into this when the article is clearly about a group that is accomplishing a well-meaning goal.
The other group is saying they want equally and accuse the first group of supporting discrimination for having single-sex organizations.
One can accuse the first group of assuming bad faith or the second group for building strawmen, but all that does is signaling which group one identify with. It is unclear how to find common ground when both groups clearly has the same goal but have polarized opinion in how to get there.
I'm not saying that they shouldn't be allowed--go for it--but I don't consider them ethical.