... Noticing a trend here?
There are good reasons why one might want and even need X-only space at a public event. Queerspace, People of Color Space, Parents of Children with Special Needs Space, Womynspace, People in Recovery Space - many of us could benefit from spending time among our peers and talking shop with folks who have shared our struggles. But in all this I see one major issue: who gets to decide who qualifies for admission to exclusive space?
I have no problem with a workshop/ritual organizer saying "while we thank and cherish our allies, this space is for [x = women/queer people/people of color/sexual assault survivors/people in recovery/etc.]. we ask that you not attend if you do not identify as [x]." But are the organizers at Pantheacon, or any other event, ready to weigh in on questions like "is a transwoman a 'real' woman?" or "is that person who 'looks white' really a person of color?" I see no easy answer to that question and I see it coming up more and more as we become an increasingly multicultural, multiracial and multigendered society.
I might also note that one can question behavior without criticizing identity. The wannabe James O'Keefe who shows up at the People of Color circle to protest racial discrimination against the disempowered and disenfranchised straight white male can be ejected for acting like an asshat without addressing his claims about his black twelve-times-removed great-grandfather. So it is possible to be inclusive without tolerating outright disruption and hostility against the group's original raison d'être.