This is interesting and also unsurprising. Haskell is an abstract and high-level language and so doesn't dictate irrelevant machine details as C does. The only reason C's considered efficient at all is due to what was effectively a meme from forty years ago; there have been lifetimes of human effort wasted making C fast, only to trivially be beaten by someone using better tools. A proper analogy would be beating the world's faste runner in a mile-long dash by using a bicycle or perhaps using a cart being more efficient than carrying items on one's head; the main difference is people haven't been deluded to think that humans are faster or better at carrying cargo than a creation of mankind.