You are right in that the USD is far more digital than what many imagine.

What is money? We know that money is not a small sea shell, a notched
wooden stick, a metal coin, or even a printed piece of paper. We know
money isn’t any one of these things, because the notion of money has
survived the obsolescence of all of these things.
Common Cents -Tony Cerrato

Money is not a medium of exchange, it is a method of measuring commercial value.