People are interesting, and religion is a thing people do.

In this case there is quasi-religious imagery but you as the reader aren't actually supposed to be mystical about the god/devil in the story the way the characters themselves are. It's not C. S. Lewis

Do you also find LeGuin uninteresting?

I mean, it's not my fandom, but Catholics do have a wicked sense of symbolism and decoration. Hyperion wouldn't be as colourful if Simmons used a bunch of Evangelicals instead.

Well, i detest jihadism, but still could enjoy dune