The Guardian: the moral of King Kong is simpler still: "Don't pick a fight with nature."
Letters to an Unknown Audience: The message of Narnia is clear: Don't ask questions. Trust the first person you meet and stick with it. Raise your ill-begotten sword for it.
I haven't seen either, but I'm curious to what extent these morals are injected by the films' creators vs. viewers. I also think it would be an interesting thesis project to compile a list of morals as described by film critics over a few decades, correlate those morals to political party platforms with some sort of text similarity analysis, and then measure ticket sales against election results.
But to whatever extent people are questioning the morals of Christian movies, I don't thin it's surprising, as religious movies imply a specific emphasis on morality that secular movies do not.