There is a big difference between what sex you are and what beliefs you profess: The first should not be determined by how rational you are, while the second very much should. There should be nothing surprising about the fact that more intelligent and more rational people would have different beliefs about reality than less intelligent and less rational people.
Or to put it another way: If you believe that all political affiliations should be represented equally in the sceptic/rationalist community, you are implicitly assuming that political beliefs are merely statements of personal preference instead of seeing them as claims about reality. While personal preference plays a role, I would hope that there's more to it than that.
There is a big difference between what sex you are and what beliefs you profess: The first should not be determined by how rational you are
But it might affect how rational you are.
A long blog post explains why the author, a feminist, is not comfortable with the rationalist community despite thinking it is "super cool and interesting". It's directed specifically at Yvain, but it's probably general enough to be of some interest here.
http://apophemi.wordpress.com/2014/01/04/why-im-not-on-the-rationalist-masterlist/
I'm not sure if I can summarize this fairly but the main thrust seems to be that we are overly willing to entertain offensive/taboo/hurtful ideas and this drives off many types of people. Here's a quote:
The author perceives a link between LW type open discourse and danger to minority groups. I'm not sure whether that's true or not. Take race. Many LWers are willing to entertain ideas about the existence and possible importance of average group differences in psychological traits. So, maybe LWers are racists. But they're racists who continually obsess over optimizing their philanthropic contributions to African charities. So, maybe not racists in a dangerous way?
An overly rosy view, perhaps, and I don't want to deny the reality of the blogger's experience. Clearly, the person is intelligent and attracted to some aspects of LW discourse while turned off by other aspects.