People crave certainty.

I think its slightly different I’d say its closer to: People crave simplicity.

That can frequently mean certain answers, but even if the answers aren’t certain, but simple, they accept it. This is the root of most conspiracy theories. It is much simpler to accept that a global cabal is specifically trying to convince people the Earth is flat rather than accept that we live on the surface of a very large round planet, that “down” doesn’t always mean down, and that gravity exists to prevent people on the “bottom” of Earth don’t simply fall off into space.