While I'm writing bitcoin's value is around 1700$ and of course is the first thing that we consider when we search them on internet.
First. Bitcoin like any other cryptocurrency could in a certain way substitute classical fiat money.
It simply means that who posses them may effectuate a purchase and sending a certain amount of value.
This amount of value take form when the counterpart accept this method of payment and a transaction has settled.
Second. The nominal value is different from the real value. What do you mean ?!?!?
Well. This aspect hits especially normal currencies because when a change happens and its value increase or decrease, one currency becomes more strong than another one.
In other words a currency of a nation increases in value and now who wants that currency have to pay more to obtain it.
This is called "nominal value" and it not direclty effect real world.
We are interested in "real value" because it tells us how much power, in the real world, has a specific currency in a specific nation at the moment when I want to buy something.
Bitcoin subtract itself from countries problems, because essentially bitcoin is a currency but it is not bound to a country's economy altought I can exchange my BTC to normal fiat currencies like USD.
Third. Take it simple. Take the daily volume of stock market and compare it to the daily volume of forex market.
well. As you can see there is no way.
Currencies are the mirror of liquidity, goods at liquid state.
Stocks are companies that try to catch profits in their own niche.
What could happen if volume of fiat currencies will start to transact heavily to cryptos?