Family, region, and occupation may describe someone's background, but good character appears through chosen actions. It is evident in respecting service workers, acting fairly during disagreement, and protecting the rights of those with less power.
A prestigious surname does not excuse broken promises or harmful conduct. A person unknown to the public may nevertheless deserve high regard for integrity.
In حُسْنِ الْخُلُقِ, the first noun is the head of an iḍāfah construction and the second the genitive complement: “goodness of character.”