"Let me be more precise: the middle class has only shrunk because people have moved from X to Y, where $25k < X < $75k and Y > $75k. I.e., no one became poorer,

"Let me be more precise: the middle class has only shrunk because people have moved from X to Y, where $25k < X < $75k and Y > $75k. I.e., no one became poorer, and some people became richer." Again, you haven't shown this, either. Many people could have gone from $65k to $35k while a few moved from $65k to $650k on the same set of facts. That nobody has dropped below the baseline of the middle class does not mean it is not shrinking or that nobody in it has gotten poorer. "You still have yet to show how people's income exceeding $75k causes any harm at all" This is not the point. The point is that massive wealth inequality causes the harm. A shrinking middle class is a symptom of that inequality. Whether or not you continue to deny or justify the symptoms is not going to change the facts of the underlying disease. I'm not going to show you how dying causes cancer.