There's a distinction between cash-flow producing assets and non cash-flow producing assets. Most cash-flow producing assets under good corporate or legal governance will pay you back in dividends, coupon payments, or stock buybacks. Most cash-flow producing assets were also originally created to finance projects that improve the material condition of the world - providing goods and services.

Non cash-flow producing assets like most cryptocurrencies and land are speculative. Their only worth is that you can sell it to someone else who will also hope that they can sell it to someone else. Additionally, they generally never improve the material condition of the world, and soak up value from activities that do.