There a ban on talking about religion on Lesswrong that I'm aware off. I'm aware off a ban on talking about the basilisk and a ban from talking about advocating specific violence.
Could you point to an discussion in which Lesswrong supposedly agreed that talking about religion is wrong?
I think it's more of a matter that this community lacks people who can make interesting arguments in favor of religion.
The last interesting discussion about religions on Lesswrong I remember was how the catholics scored best on the reverse ideological turing test. I think that making arguments on that level about religion is welcome on LW.
Sorry, the "...talking about religion because it's wrong" should have said "talking about the validity of religion because it's wrong."
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.