How to Restructure the Concept of Maritocracy in Our Society?

We want to neatly divide things up into morally deserving, rewardable effort and circumstances beyond our control. But what happens when some of the circumstances are our biology, and they create our brains that are producing the effort? I don't think once you start thinking about the development of a human life, that distinction we want draw between things we things we can be rewarded for because we have control over them just kind of falls apart. It really doesn't make sense developmentally, which people don't like.