Perhaps I wasn't clear, but the phenomenon I'm describing is one in which the credit market grows to become more important than the metallic market and eventually destroys it, because in order for the bank trying to calm the crisis to credibly maintain that discount window open, it will need the power to create money in unlimited amounts (not actually to create it, but to convince investors that it can create it).

So what happens is that when credit markets are in their early stages, they go through violent disruptions every few decades that get more and more intense as the credit markets grow, and at some point, the survival of the economy as a whole is at risk, and sometime before that happens the government says "enough. We need an elastic money supply that can guarantee that bills remain discounted no matter what. We have to put an end to the cascading failures due to panics/manias in the credit market." That's when the metallic market is replaced with fiat.

So while you often hear how every fiat currency fails, you don't often hear how every metallic currency is replaced by fiat, and I'm trying to describe this process -- that functioning currency markets inevitably give rise to credit markets, and it's the credit markets that are required for capital investment and economic growth, not the currency markets. Thus the need for stable credit markets is inevitably what drives the abandonment of metallic or any other kind of inelastic money -- of which bitcoin is an example.

This is not to say that inelastic goods can't survive as a tradeables. Stamps even survive as tradeables. So do paintings. But they don't survive as currencies in an industrial economy that requires a large, steady flow of capital investment.