Well, along with medical research, organ donation and cryonics also probably exceed the expected utility of cannibalism or necrophilia.
That said, I’m not sure they would be mutually exclusive. My head for my future self, my innards for the sick, my penis and anus for lovers, and my arms and legs for the hungry.
More strongly, is there any reason to believe that people are more likely to “click” to rational beliefs than irrational ones?
As an example, papal infallibility once clicked for me (during childhood religious education), which I think most people here would agree is wrong, even conditioned on the existence of God.