1) People of different races provide different perspectives so we shouldn't make them feel excluded.

Well, religious people also provide different perspectives, and this effect is much stronger for religion.

We can't avoid the perspective of religious people, because they are the vast majority of the world. So there is no special need to make them feel welcome (nor is there a special need to make them feel unwelcome). Also, if we look at this in terms of networks of evidence, the rationality node screens off everything from religion, which is not at all true of the perspectives of women and people of color.

2) Not making people feel bad is intrinsically valuable.

This applies equally to religious people.

Have you read the comments to this? This is where the history and state of the world come in. If you are a religious person, and you are bothered by Less Wrong, hey, there's very nearly the entire rest of the world for you to feel comfortable in. But if you are a woman and you are bothered, where can you go? There is no place on earth free of sexism.

Also, of course, some religious people are offended by the very existence of atheists who are vocal about their beliefs. It is, of course, hard to get them to admit this -- usually, it is framed in terms of "tone". But "tone" is a function of the listener as much as the speaker, and when someone's views are being attacked, they are more likely to hear the tone of the argument as angry. Similarly, it can be hard to hear the difference between "You're wrong", and "You're an idiot."

I do think that the comments on Less Wrong sometimes go out of their way to attack religious people, and I do think that this is an error. But I don't think you could have Less Wrong without having a population of vocal atheists. We could, however, do entirely without the vocal racism.