A child's intellectual development is largely shaped by his surroundings and it often depends on the environment in which he grows up. There is also a matter of genetics. The way children used to learn from mistakes physically is now being reversed. Today, the brains of many young people are updated. Although patience is very low among this young generation, they can use their brains properly in many cases. On the other hand, the experience that older people have also takes them much higher in terms of reality.
I don't think this is true. We started farming 10,000 years ago, yet our brains still tell us to crave sugar that we can now get easily. Evolution is very slow.