Religious opinions are divisive, we took our side, and don't seem to be considered very highly by those who took the other.

I don't mind closing the community to believers, in first approximation their ideas are worthless. But I wouldn't extend that to liberals, libertarians, conservatives, environmentalists, anarchists, etc.

I can't think of any other topic beyond religion and politics where it's commonly expected that everyone has a position - some people can have strong and conflicting opinions on say parenting styles or whether Esperanto is a real language or interpretations of quantum mechanics or operating systems or whether Batman could beat Superman, but they don't go around saying "Oh yeah he disagrees with me because he's a yellowist" or something like that.