That’s what the guy said. Money isn’t “intrinsically” real - it doesn’t have something in-and-of itself. It’s extrinsically real - it represents something in the society we live in, a system of arbitrage and barterage that we use to represent an amount of work (Poorly, and with little benefit to a large number of people).

So no - if the extrinsic reality changes, then the barter or arbitrage currency will change - bottle caps, for instance, take over. But for a large society to function, a commonly accepted means of representing “value” has to be agreed upon. I can’t just say, “Well, I’ve got the worth of x hours worth of time spent on projects to provide”, instead I’ll say “I’ve got x pounds to provide”.

Originally, this was made more explicit, and it still exists on UK currency: “I promise to pay the bearer…” At that point, the notes had a (Bank-enfornced) intrinsic value. The words meant a promise to provide the currencies face-value in Gold. Now, we’ve done away with gold-backed currency, and the raw value is arbitrary, it has no intrinsic value but that set by extrinsic realities.