Central bankers, in particular the Federal Reserve, are those primarily responsible for the mess in which we find ourselves. Their key error was to claim that asset prices did not matter and, to make things worse, by acting as if they did matter when they fell but not when they rose.
This policy drove the US stock market to its most overvalued level ever in 2000. When the bubble burst, it required a big cut in taxes and extremely low interest rates to prevent the economy from going into a major recession.