Ah, there is the point exactly of the article exactly.
Except that the point has nothing to do with religion; it has to do with the essence of liberalism, which is that a liberal likes feeling good without regard to the content accompanying the feeling.
The swaying libs WERE NOT dreaming of a world without religion. The song does -- they were not. Many of them are very religious people.
What they were doing was dreaming of a sweet utopia. It made them feel good to so dream. (As it should.) They were not aware of the lyrics, except as a general idea. Such an awareness would not be desirable, since it would BREAK THE SPELL.
That there is OBJECTIONABLE CONTENT associated with the dream does not bother them. They are liberals. The end is a good end. The dream is sweet. The song is pretty.
Like many on this thread, they would say, to this article "it's just a frickin song."
And that is the essence of liberalism. As long as we can feel good, let's get too hung up on the analysis.