Wait, what?! Is "a story where the protagonist behaves rationally" really a new genre of literature? There is something horribly wrong with this world if this is true.

Yup. At least sort-of. If you haven't read Eliezer's old post Lawrence Watt-Evans's Fiction I recommend it. However, conspicuous failures of rationality in fiction may be mostly an issue with science fiction and fantasy. If you want to keep the characters in your cop story from looking like idiots, you can do research on real police methods, etc. and if you do it right, you have a decent shot at writing a story that real police officers will read without thinking your characters are idiots.

On the other hand, when an author is trying to invent an entire fictional universe, with futuristic technology and/or magic, it can be really hard to figure out what would constitute "smart behavior" in that universe. This may be partly because most authors aren't themselves geniuses, but even more importantly, the fictional universe, if it were real, would have millions of people trying to figure out how to make optimal use of the resources that exist in that universe. It's hard for one person, however smart, to compete with that.

For that matter, it's hard for one author to compete with an army of fans dissecting their work, looking for ways the characters could have been smarter.