How much money is enough money? How many vacation mansions does one family need? Some people have way too much money. There's vast and growing wealth and income inequality. If everyone was alike, it would be a more boring world, but too much inequality is the other bad extreme.
Income inequality is often justified by the need that business has for capital to run the business. Someone doesn't need hundreds of millions for personal consumption, but the budget of a business may need to be in the millions, or the billions to meet the payroll and build the facilities that house the business.
If the money is invested in a business, that money is needed. Tax discussions need to take this into account, but for "pure luxury personal income," some people make way too much money for the health of society.