If you’re talking about usury, then you have confused investment with lending. Lending money is not investment. When a bank gives you a loan, they aren’t investing in your house. They’re supposed to be helping you buy a house. Interest on a loan is theft as no value is being provided by the bank in return for that interest (as opposed to service fees for the labor of issuing a loan, for example).

Some call capitalism state-sponsored usury. I’m not sure I’d go that far. But money is sterile, “barren metal”, as “The Merchant of Venice” calls it. It cannot multiply. Only labor multiplies value.

Wrt the article, while the author does seem naive and no systematic thinking is demonstrated, you could store away valuable commodities, like gold. But it won’t breed for free. For more gold, you must work, or steal.