Money has three functions : unit of account, store if value, medium of exchange. Cryptocurrency isn't great at the first two, but if we presume the scaling problems will be solved then it is pretty good at the latter because it doesn't require you to trust the banking system. So there is an unbundling of the functions of money described by Eugene Fama originally and then tidied up and better articulated by Tyler Cowen and Randall Kroszner in their book on the New Monetary Economics in about 1992.

Its completely irrelevant what the price of Bitcoin is for its usefulness as a medium of exchange.

This medium of exchange aspect is very important because it makes banks no longer special since its possible in time to make payments without a banking system. Thus the role of the state in regulating banks can disappear eventually - no deposit insurance, no bailouts and no too big to fail.

Credit can be provided by funds because the information asymmetry of banks no longer applies when you can port your banking records via API.