[dvanduzer]

Yes, that is the core thesis of the article.

For the last 30 years, that tiny fraction (0.1%, correcting what I assume was a typo/misread) has seen their overall share grow.

Thirty years ago, that 90% possessed 35% of the wealth. Today, that 90% possesses 20% of the wealth.

The 9.9% near (but not at) the top has maintained their wealth over the last 30 years.

The culture problems of this tier of American society may not be as obvious to you, but I assure you, the answer to your question is yes.