Compare North and South Korea.
The North demands that you do not learn anything except the limited amount they allow. Real education is verboten although they do emphasize "re-education". They are a failed society.
The South does put emphasis on education and learning. They are a successful society.
They are perhaps the clearest example of the difference that culture has on people. If genes ruled then the North and the South would be roughly equal. They are not.
Wade never said that genes are the only decider of how people live. But they are a major driver. If genes played little or no role in people's lives/futures, then there would be little or no disparity in how different people live or what they earn within a society. You are putting the cart before the horse. In a free society, people determine their culture...not the other way around.