Do you really think someone's ending point as an adult is largely limited to their "brains"? Like, how are you going to completely exclude the upbringing environment and the scarcity and struggle for resources that some folks face.
You reiterate my question in the second sentence: How do we weight these different privileges?
Perhaps, but the paper also concludes "that the importance of the role of IQ in predicting life success should not be overestimated". Furthermore while IQ did to some degree predict objective life success it does not seem to predict subjective life success, ie how happy you are with how your life turned out.
It’s the best individual predictor when compared against other predictors, but not very predictive on its own.
I.e. Iq is more predictive than inherited wealth, but iq + inherited wealth is more predictive than either individual factor.
Class traits are of course inherited, but there is a distinction to be made between cultural inheritance and generic inheritance.
Which are you talking about?
>For instance, IQ was believed to be one generic measure of human intelligence, on which Young’s meritocracy was based. But a century of research on IQ and life success has largely dispelled the once widely spread myth about the importance of IQ (Arrow et al., 2000; Gardner, 1983; Goleman, 1995; Gould, 1996; Zhao, 2016). Based on longitudinal studies on IQ and life’s success that lasted multiple decades, researchers conclude that: “the value of the IQ scores should not be overestimated” (Firkowska-Mankiewicz, 2002, p. 41).
https://spssi.onlinelibrary.wiley.com/doi/pdf/10.1111/josi.1...
Besides that, even if an analytical weighting cannot be given, it doesn't mean we can't examine the effects qualitatively.
>The results demonstrate that intelligence is a powerful predictor of success but, on the whole, not an overwhelmingly better predictor than parental SES or grades. Moderator analyses showed that the relationship between intelligence and success is dependent on the age of the sample but there is little evidence of any historical trend in the relationship.
https://www.sciencedirect.com/science/article/pii/S016028960...