the relevant cost-benefit calculations.

My claim is based on historical analysis. Historically, the ideas that benefit humanity the most in the long term are things like capitalism, science, the criminal justice system, and (to a lesser extent) democracy. These ideas are all based on aligning individual self-interest with the interests of the society as a whole.

Moral exhortation, it must be noted, also has a hideous dark side, in that it delineates a ingroup/outgroup distinction between those who accept the exhortation and those who reject it, and that distinction is commonly used to justify violence and genocide. Judaism, Christianity and Islam are all based on moral exhortation and were all used in history to justify atrocities against the infidel outgroup. The same is true of communism. Hitler spent a lot of time on his version of moral exhortation. The French revolutionaries had an inspiring creed of "liberty, equality and fraternity" and then used that creed to justify astonishing bloodshed first within France and then throughout Europe.