Any currency that has a supply decoupled from the macroeconomy is doomed to failure as a currency, either through deflation or inflation. Deflation results in hording, at which point there is insufficient exchange and another currency replaces it. Inflation results in divestiture, at which point another currency replaces it.
Maintaining a currency requires threading a needle. Only strong governments have ever been successful at it.
Perhaps there is a technological solution, but it's not bitcoin or any of its brethren, because their growth rate is decoupled from the economy.
A currency policy that is constantly being manipulated and a money supply that is constantly tinkered with(quantitative easing?) is unlikely to keep the trust of many when there are alternatives.