What other objective yardstick is there? Long-lived groups (the Catholic Church for example) must be doing something right, while short-lived groups (Nazi Germany for example) must be doing something wrong.
OK, then: the despotic Egyptian empire lasted thousands of years, as did the various incarnations of Chinese tyranny.
We can pay special attention to the Roman Empire, which failed not because of its aggressive conquest, or its widespread enslavement of people, but for preciselt the opposite reason: the Roman leadership and citizenry lost their aggressive edge.
As to the longevity of the Catholic Church, I'm inclined to give a little bit of credit to God....
Your use of the term "objective yardstick" brings us once more to the moral implication of "atheist evolution," which yields nothing more than utilitarianism.