I don't want to say your version never happens, but there are extremely clear and consistent links between childhood trauma and mental illness, and poverty/food insecurity/homelessness are pretty major traumas to experience in childhood.

To the extent that any of us have a "healthy brain," it's because of an environment that has nurtured our cognitive development. It's a lot like how a healthy body comes from a nutritious diet and not fast food (which, not coincidentally, is why wealthy people have far fewer health problems and a longer life expectancy than people who experience poverty).

Genetics and environment interact constantly. Our genetics have some variation but our differences mostly reflect different skill sets and areas of high potential, rather than any one unitary dimension of intelligence. But our environments vary wildly. To "succeed" in our system, you need access to resources that will train and maximize whatever genetic skills you have, and point that training towards the skills that are valued by capitalism. And that's where environmental differences create massive disparities.

Having grown up pretty well-off and going to private school from third grade through college, I do want to acknowledge the pervasiveness of the narrative that our system rewards people who are smarter and more deserving. So I understand where you're coming from. But that upbringing means I've been around a lot of rich people, and I feel extremely comfortable saying the narrative is mostly nonsense. Plenty of people become rich not through intelligence but through being around other rich people and getting better access to the market. Plenty of "smart" rich people often grew up with constant attention devoted to training their brains to solve the kinds of problems that are rewarded by capitalism.

All of which is to say that I understand that you come by your view honestly, but I think perhaps you've been socialized into accepting a particular narrative. And in my experience it's very clearly a narrative that exists to justify inequality as a post-hoc rationalization, rather than a statement that has anything to do with the reality of how most people experience our economic system. The narrative is a collective emotional defense response to protect our egos and tell us we're well-off because we're special. But if we can get ego defense out of the way, the truth is pretty clear that we're mostly just lucky.

I apologize if any of this activates your defenses. It's hard to feel like maybe we've been lied to our whole lives, and we all deserve better than that.

Wishing you the space and freedom to find some truth.