I mean, we’re talking about the origin of Uruk in Tolkien’s works, which is hardly an established fact. And if we give one creator license to formulate the world as they see fit, then why not other creators, or conglomeration of creators? Would Tolkien’s changing of the Uruk’s origin from stone, to elves, to corrupted elves, be seen the same way as the original poster sees the changing of the Nerubians?