"The prime example is the Federal Reserve’s pivotal failure to stem the flow of toxic mortgages, which it could have done by setting prudent mortgage-lending standards. The Federal Reserve was the one entity empowered to do so and it did not."
Ah, but the crisis would have happened in the absence of the Federal reserve. In fact, one could easily argue that the Fed was lobbied heavily, HEAVILY to do less by external forces and those forces succeeded. You cannot come to the conclusion that a lack of a Fed would have made markets more stable.
Without a centralised monetary authority you lose an important tool to manage a crash.
Actually you can. The modern central banking system is all part of the same homogenous system, coordinated by the Bank for International Settlements (BIS) in Switzerland, the umbrella bank for all central banks in the world.
But Central Banks have the ability to make a huge difference in the quality of life/standard of living in a country depending on its competency and understanding of the economy. If you take the US as an example and compare the response to the 2 greatest financial crashes in the last century. The Fed in 1923 operated under poor information and took the exact wrong course to mitigate a financial crash by contracting monetary supply. Contrast with the Fed in 2008 to date (despite complaints) - its steps in producing massive quantitative easing was the exactly right thing to do. Given their likely responses, there are many more jobs and more economic output today than would have existed had we swapped the 1923 and 2008 federal reserve - I don't think many economists will disagree on that point.
With a decentralised currency like Bitcoin, my understanding is that monetary factors cannot be controlled. So you'd lose a very important tool when it comes to regulating the economy/applying course corrections over economic cycles.