The problem IS the centralized authority. Can you forever trust a government to not artificially inflate or deflate the value of a currency? The whole point was to have a system with no single authority. No single point of failure.

It is, however, not perfect. The volatility, limited number of transacrions per second , and reliance on an incredible amount of energy expense were the largest of these when the original bitcoin concept was created. Some of these issues have solutions, but its still an evolving technology.