I guess it's a part of that larger "everyone before us was stupid" thing that seems big now, but I promise, the major names in religious thinking were brilliant. There is something to believing in something greater than what we see, and when you go on atheist forums, they never really seem like enlightened or happy places.
I don't really have a cogent argument here, but this smells like 1950s Utopianism, where everything that went before was considered obsolete, and many of the good parts of culture and our cities were just thrown away in the name of progress.