The poster makes one excellent point:
If they are anything like the anti-pluralist, anti-tolerance, and absolute certainty evinced by posts all over this forum, then they deserve liberal criticism of this sort, just as much as anti-pluralist religious claims deserve that criticism. ...
But when you get into the territory of finding those you disagree with inferior, worthy of no toleration or civility, and are convinced that your side is inherently smarter and that the world would be better off if everyone agreed with you, then you are as deserving of liberal criticism as any theist who shares that general approach to life.
Except for the "absolute certainty" bit, I have to pretty much plead guilty as charged. At the level of discourse, I'm definitely anti-pluralist and anti-tolerance. I do think that atheism is a more intelligent, more rational position than theism, and theists are typically less intelligent than atheists, at least when they're discussing religion, and often in general. To paraphrase J. S. Mill, not all theists are stupid, but most stupid people are theists. I do think the world would be better off (although of course not perfect) if everyone did in fact agree with me: If you don't think so, why bother believing anything?
(Of course, at the level of law, I'm quite tolerant, pluralistic and civil. I don't support making theism illegal nor do I advocate any sort of violence or economic coercion against theism, unlike some theists regarding atheists.)
The thing is, atheism is true and theism is false. Theism is all lies and bullshit. Why should I tolerate lies and bullshit? Why should I not consider lies and bullshit to be inferior in every way, intellectually and morally, to truth and honesty? Why should I tolerate con-men and parasites dressed in robes and collars selling "God's love" any more than I should tolerate con-men dressed in sharp suits selling the Brooklyn Bridge?
It's very amusing (once you get past the tooth-grinding hypocrisy) to see theists—usually the most judgmental of people—espouse this sort of judgment-free ethical relativism when it is their own ox that is gored. They can't defend their position on its merits, so they have to descend into the worst sort of postmodernism in responding to their critics.