We know that high demand and low supply means soaring prices. Because the supply is fixed to 21 million BTC, block reward (currently at 12.5 BTC per 10 minutes) will eventually disappear and miners will lose their biggest source of income.
All money currencies will disappear in the future, including Bitcoin. This is because the system of money is a flawed and tired system. Human kind is simply waiting to be taken them out of the dark ages where so-called civilisations use money and a trade-based system.