I sorta knew much of what the author writes, but it's still a bit shocking to see it laid out, in hard numbers, that many consumers at the lower end of the income spectrum no longer matter in the US economy:

> What we do see are troubling signs that low- and middle-income consumers are fading in the economic data. The top 10% of earners now account for about half of consumer spending, the highest share since at least 1989, according to an analysis by Moody’s Analytics. The top earners’ share of spending has trended higher since the early 1990s from a low of 35%, matching a rise in income inequality over the same time. Meanwhile, the bottom 60% of wage earners account for less than a fifth of consumption, down from more than 26% three decades ago.

Having such a large portion of the population not matter anymore, from an economic standpoint, doesn't seem... sustainable.

In a way, if you allow me some liberty with the concepts: as finance and the real economy drift further apart in their metrics, at some point that divergence creates a crisis.

There are academic articles on that such as [1].

[1] "Crisis and the Role of Money in the Real and Financial Economies—An Innovative Approach to Monetary Stimulus" <https://www.mdpi.com/1911-8074/14/3/129>

This is obviously what happens as an entire population becomes very rich. Necessities no longer show up on total spending because most spending is on luxuries. And luxury pricing obviously is non-linear.