Let's make some real calculation: Each month, you borrow $100 to buy food, and those $100 goes to the food company as income, and food company put $100 to bank, and bank loan out $90 (10% reserve requirement) to another borrower, he spend all $90 to buy products from your employer, your employer have $90 income, and he is so generous and gives you all $90 as salary. So, how could you payback your $100 loan with $90 salary at the end of the month?
The reason these examples are stupid is that they assume that one person holds all the money in the world and that value can only be traded using that money. Of course, neither of those assumptions are ever true.
Ok, lets assume that 7 billion people holds all the fiat money in the world and value can be traded using those money. Did that change the way how it works? Putting billions of semi-conductor components into a CPU does not change the basic electrics theory that you can prove in a flashlight