The central bank is on the Gold Standard. The discovery of new gold increases the supply of gold, which causes an inflationary boom. People blame the inflationary boom on the gold discoveries. It can't have been a monetary shock, because the central bank wasn't doing anything different from what it always does. The central bank "did nothing". Gold mining needs to be a regulated industry to prevent this happening again.
Or a sudden fashion for gold jewelry increases the demand for gold, which causes a deflationary recession. People blame the deflationary recession on the fad for gold jewelry. It can't have been a monetary shock, because the central bank wasn't doing anything different from what it always does. Regulation is needed to control bubbles in jewelry markets.
In those two examples it's easy for us to see the fallacy. It was the gold discoveries, or fashion for gold jewelry, given the Gold Standard, that caused the monetary shock, which in turn caused the macroeconomic fluctuations. It's easy because we don't see the Gold Standard as "normal"; pegging the price of gold is not the way that we nowadays frame monetary policy. We don't use the price of gold as our measure of whether monetary policy is "tight" or "loose". And we are pretty sure that those two shocks would have had little macroeconomic effect if the central bank had a more sensible monetary policy than the Gold Standard.
But it might be a lot harder to see the same fallacy created by our own frameworks for thinking about monetary policy.