If you look at income distribution its a hockey stick - you really have to slap yourself on the face and realise there is no middle class - what you thought of as professional-middle-class-contributor is actually college-debt-burdened-lower-class - no matter how many years they work they will never pay off their debt, let alone own their own home.
People aren't asking for "income equality" they are asking for some level of humanity and democracy to be restored to our version of Capitalism, to strengthen that capitalism.
So, just as "All Lives Matter" is not a good response to the "Black Lives Matter" movement, its not useful to discuss "income inequality is not intrinsically a bad thing" when we are in a time when the lower class are basically slaves and the middle class has been in steady decline - your _only_ chance to have security is to win a lottery [ the Startup or the PowerBall variety ]
So, what needs to be talked about is rather : how to take money out of politics, how to get poor people out of the ghetto, how to stop young black people from being shot by police on a weekly basis, how to bring back a reasonable level of tax on the super wealthy, and how to stop large companies from getting subsidies to pollute our environment.
A small amount of Socialism is needed urgently to bring Capitalism back into a survivable form - if not, I really think we are headed for bloody revolution, because most of the populace are angry, and its a rational anger because their survival needs are barely being met, in many cases.