Gini index = 0 refers to an economy where gross income has been redistributed so that all income earners in the United States received the same income, equal to the most current measure of the mean (not median) personal income in the United States. That is, the aggregate personal income will remain unchanged.
We'll assume the Federal income tax brackets remain the same as in 2015.
Given the above assumptions, will Federal tax revenue increase or decrease compared with the present day income distribution, and by how much?
Bonus question: Is there an optimal distribution of gross incomes in the United States working population that maximizes Federal income taxes?