Yes, this is my primitive understanding of economics. just like first law of thermodynamics, which states: "energy can neither be created nor destroyed, only altered in form".
I do believe economics is not different. There is a limited set of value in the world created by humans (service, knowledge) and Universe (minerals on Earth, energy coming from Sun and so on). We give price for the value using currency. If currency moves to a limited set of people, it should be taken away from others. When bank hands off mortgage, it expects something in return, which is an interest. To pay interest you need to provide service for someone, more scalable your service is, more you can earn, but not all services are scalable, for example teaching at schools, it doesn't scale, because it has physical constraints, like having a teacher who can engage with kids, whose primary concern is not meeting ends in their private life.