What he says is very true. Even if one looks at management principle 'Management by Results' Chappel should go. To elaborate, he had enough powers to influence selection and hence he also should be a party to take 5 to 6 openers to World Cup sacrificing middle order, dropping Dravid to lower down the order, destabilizing the batting further.
He might not have done it intentionally but the results were devastating. Whether the other players played to true to their role or not and should go or retained is another topic of discussion.