Anduin now has a spidey-sense that guides his judgment and we see a lot of Light-related stuff like Alonsus Faol, Calia and the resurrection of the latter into a holy undead of sorts. Perhaps that was the prime purpose of the book, to establish how broadly people accept the Light as something that's good and natural around them, that even when a previously unthinkable thing such as a holy undead happens, they immediately accept it because it's Light-related. The book's over-emphasis of the saintness of characters other than Sylvanas would be looked at differently, if we learn they are like that, because they are blind the danger right in front of them and their actions are discreetly nudged by the Light. Calia's sudden realization and dedication to help her people defect and Anduin's spidey-sense in particular feels like manipulation.