Progressive taxation actually does the opposite of its intended effect It slowly corrodes away at the middle class. This is because it restricts the market's ability to restructure which allows for mobility from the lower class to the middle or upper portions and vice versa. To understand this, think about the flow of money. If you tax the upper portion of the tax brackets for higher amounts and the money gets funneled back to the lower class, the lower class are already in debt and having very little savings. So the lower class uses the money in the only way it can.... to survive. The lower class spends the money on the commodities that it needs to survive which isolates these certain commodities and resources even more as being absolutely crucial. The taxes end up becoming a battery for the upper class/rich. Prices on these commodities will go up and it slowly erodes the middle class.
In the end it is very much like Jenga, you remove blocks from the middle and place them on the top.