>If you're poor, you hang on to stuff, because it may come in handy. If you have enough money and some left over, you can get rid of stuff, because if it turns out you really needed one of the things you got rid of, you can buy a new one. But if you can't afford the new one, you keep stuff "just in case".

Yep!

This is my exact argument for why minimalism works well for more well-off people.

If you can afford to buy a $3 screwdriver again, why keep it around if you only use it once a year. It is just clutter.

There is another argument of using Craigslist as storage (sell what you don't need, buy it back when you need it). It also relies on having free money to be able to do such a thing though.