Correct. Even the worlds richest man can't buy an internet company without going into debt (or crashing the stock which their "richness" is derived from)
In the U.S at least, holding cash is considered the worst thing to do if you have wealth. Which then leads people to use debt
Although Warren Buffet isn’t the richest, he surely can buy things with cash. In his last annual report, Berkshire reported 33 trillion in cash if I remember correctly. They didn’t find anything interesting to buy for a fair price so then they’ll just sit on their hands.
33 trillion would be more than the current US debt. It'd be more than 10 times the market cap of the most valued company. It'd be more than the combined market cap of the 100 most valued companies globally (seems to be at around 32 trillion for all of them).
The tl;dr is that humanity has at least an 80,000 year history of goods which are fungible, collectible, portable, scarce, and made to an exact standard, traded between people who may not speak the same language for any other sort of trade good. The familiar example is wampum, but the practice predates the colonization of the Americas by many multiples.
Debt is where state money comes from. But shell and hunk money is where states got it from, and the systems coexisted into the late 19th century.
In the U.S at least, holding cash is considered the worst thing to do if you have wealth. Which then leads people to use debt