For a professor of economics at a major university, this is a remarkably shoddy piece of thinking. The author finds great significance in the fact that Tom Brady's diet is about the same as the average American's. How about Tom Brady's health care? If he gets cancer, will he likely be bankrupted by it? Or his financial security---if he can no longer work, how much will his lifestyle change? Other examples are similarly flawed: he's impressed because his new Suburu is almost as good as a Mercedes! Well, perhaps he should try driving an '88 Corolla with no muffler and 300,000 miles on it for awhile.
The debate over income equality isn't about a falling standard of living in any absolute sense. It's about how the world's increasing wealth is distributed. And more and more of it is going to the top 1%, despite the complete absence of any evidence that they are actively generating a greater proportion of it than they have in the past. The reality is that wealth gets distributed along social networks, and the idea that this distribution corresponds to value actually created is a fantasy.