It’s a metaphor for climate change, so the ending of the book would make little sense in this context, where the catastrophe is real. The point of the film is whether a parent is willing to sacrifice their own life to make the world a livable place for their children. Most parents would.

The bad faith arguments around this film are really weird.

I don’t remember the film even mentioning the catastrophe being caused by God. I saw the film as more of a universal reckoning in line with cosmic horror. Nature needing a sacrifice made on the basis of love as an act of protest against the otherwise senseless cruelty of humankind. I thought it was good.