>"Individuals don't care about their ability to change their percentile, they care about their ability to change their total income" This is completely wrong.

>"Individuals don't care about their ability to change their percentile, they care about their ability to change their total income" This is completely wrong. People care intensely about their pecking order (looks, money, accolades, etc). Beyond this, there are purely functional reasons to care about your relative income. Limited resources lead to competition. Nobody cares if their GPA is higher than their parent's was. They care if it's higher than their peers who are trying to get into the same universities. Ditto for housing prices. What matters isn't the dollar value of the property you can afford, only whether or not you can afford to be in a top school district. Politicians don't win by being able to spend more on campaigns than politicians of the previous generation either. They care if they can spend enough to win against their current opponents. In human society, the relative comparison dwarfs the absolute.