Gold is a commodity not a currency. Historically most currencies have been either minted in or based on valuable commodities. Virtually without exception they have been produced by governments.

Do you mean to argue that no currency ever has or should have been created by a government?

So the purpose of currency is to serve as a proxy for goods and services. The basic question of monetary regulation is: "how much currency do we need?"

The Fed system actually somewhat regulate the currency supply based on the market. When you take a loan to start a business, new currency is created at the same time that a new productive enterprise is created. Gold and Bitcoin don't come from the market at all. The amount of Bitcoin added to the economy has nothing to do with the underlying economy --- its based on an arbitrary formula.