Actually, I wouldn't pick on posthuman too much because he seems to understand what you are saying more than others
He just said to keep in mind that there is a good possibility that the Arab, you are speaking to, might not mean God when he says Allah. I think that this is a good point, though you are right, we often think that when someone says "God", they are talking about God in the same manner as we think of Him. I don't really think that Einstein believed in God, but he said "God" often. From listening to clips of Einstein, he seems to suggest some cosmic greatness, but it is unclear that he really meant God.