The account of the event highlights exactly the problem with the approach taken. The guys were actually okay, but no doubt felt almost guilty for just being at an event that was billed as for women. I’ll guess that’s one reason why they did not mingle. And there are certain women in the world that would have been quick to react had they done as you suggest. I can hear the sort of responses: Oh so you are going to patronise me because I am a lesser being as a women. Why are you even here? Don’t you know this is a women’s event? Anyone can feel otherised.
Male allies are extremely important and the only way things will change in tech. Many of them have good hearts, and want to do what is best, but sometimes they need guidance. In this case guidance might have helped both achieve their goals.
What this reads as to me is, they should behave as you want them to. But as I say, the event had already otherised them…
If you read my last reply to Erynn Brook you’ll see why I think all these attempts to include specific groups only increase such otherising. As they say, the road to hell is paved with good intentions.