Vruba at Tupperwolf's little blog post Wealth, risk, and stuff points to something that has always been present in my What If I Were Filty Rich fantasies.
Poor people don’t have clutter because they’re too dumb to see the virtue of living simply; they have it to reduce risk.
When rich people present the idea that they’ve learned to live lightly as a paradoxical insight, they have the idea of wealth backwards. You can only have that kind of lightness through wealth.
There's also a followup post.