Nothing. However, there are a lot of really boring people out there, and I'm guessing that they're just okay with that.

I look at this question as a variation on the old "would anyone rather be less intelligent and happier?" question (or, "would you be happy as a Stepford person?"). All twists on the idea that ignorance is bliss. But I can't see anyone who exists outside of ignorance being willing to accept a mental "demotion" to that state.