I did not watch the video, but most creases should come out from 1. time and use or 2. if you steam them. As TonyG has said, some rugs just should not be folded. I would not say this is exclusive to any specific group or type, since each rug really should be considered if it's a candidate for folding based on it's condition and character.
TonyG - have you tried steaming the rug? If not, just be sure the rug dries properly afterward. Steam should work