I mean it's simply natural selection in a sense, no? Used to be in ancient times that what determined whether someone survived or not in the world was how physically fit they were (can they outrun a predator, overpower competition, etc.) Nowadays survival appears to be related to mental fitness. Are you gullible? Foolish? Have a propensity to blindly believe what you are told? Then you're not fit. It seems to be really that simple.

If you believe in authority figures over common sense then your genetic line will likely perish from the Earth. The only reason these people have even been allowed to survive as long as they have is due to the overabundance of resources and safety our civilization has enjoyed for a century. When the hard times come a knocking they won't make it.