So much faith.
Which evolutionary strategy succeeds is entirely dependent on the environment. Capitalism and the modern metropolis is the perfect environment for sociopaths to thrive, and research on sociopathy shows it is increasing in the West.
The simple fact of the matter is that when a sociopath is discovered, the discoverer will avoid the sociopath but WILL NOT WARN OTHERS due to fear of retaliation.
Fear keeps the sheep in check, and allows sociopaths to move from one sucker to the next. Each sociopath may only get to exploit a given mark (Mark1) two, three, or five times, but then that sociopath moves on to the next mark, and a new sociopath takes advantage of Mark1.
In this way sociopaths in our anonymous, private society run amok and their evolutionary strategy is highly successful. Sociopaths are found in large proportions among those who worked their way to wealth - ruthlessness and a willingness to exploit is highly lucrative in our private culture that has no accountability.
Dr. Martha Stout in The Sociopath Next Door gives the example of a sociopath who lied and blackmailed her way into a position as a clinical psychologist in a mental hospital despite having no qualifications.
Colleagues and patients became aware of the sociopath on multiple occasions, but when they would complain to the administration they hit a stonewall because the forward-looking sociopath had sexually blackmailed key individuals.
The sociopath worked as a psychologist for 14 years before a wealthy and connected patient was exploited and harmed by her, upon which time the wealthy patient's father threatened the hospital with a public lawsuit if they did not pay him.
The hospital administration paid a settlement to the wealthy client and fired the sociopath, but did not report the sociopath to ANYONE, including its own staff. The sociopath then simply went and worked at another hospital.
Over and over again in our society the pattern of the sociopath is that when they are discovered they simply move on to the next sucker.
This did not happen in traditional cultures. Dr. Martha Stout explains how in Inuit culture sociopaths would be ritualistically murdered by a group of men in the tribe. In 19th century America, if a sociopath scammed some people in a town, those people would capture and lynch the sociopath even if they did not engage in strictly illegal behaviour.
This selection pressure prevented the proliferation of sociopaths, but now our society rewards sociopaths and has no protective mechanisms. More often than not, sociopaths use their lack of conscience as a business advantage and rise quickly in organizations through charm, blackmail, politics, and ruthlessness.
We live in the age of the sociopath. Bad people are not punished but rather rewarded at every turn. A huge proportion of corporate and government leaders are diagnosed sociopaths, and they got to where they are because the good people they fucked over along the way either did not speak up or were ignored and ridiculed when they did.