You actually seem to be pretty much in agreement with the person you originally replied to. I only read you as calling out a few more specific examples of what causes anxiety but it’s completely possible they are encapsulated in quote “etc.”.
If you're always questioning if you're happy enough, you'll never truly reach happiness.
So one obtains shelter, and healthcare, and an education, and all those things you listed. And they're still not happy? If cake is the baseline, is more icing going to make that much better?
I have observed that people who reach that state aren't looking for "more money" so much as they are looking for something that is more fulfilling for them personally. And the article observes that as well.