We have a confession! It was made by Michael Edmondson, and it was produced by the people behind Expelled. He wrote to me, and says, "The intent of the video has been questioned a lot…I suppose the answer is that I tried to make something that was funny to me and It's not really meant to convince anyone of anything." That's how I felt about it: it's amusing, and that's all that matters — it's vague enough that it can be read any way you want.
Edmondson has also made a brief sequel.
Note that Stein is wearing a t-shirt that says "Poe's Law".