I agree that Keynes was right in his analysis and his proposals for optimizing the performance of the existing economic system. The need for managing the economy arises from its inherent instability. That instability exists because all of the variables in it, to include money, are too interdependent.

That is a structural problem. Managing the economy is at best treating its symptoms.

An actual cure for instability would be a fully exogenous supply of money sufficient to govern the economy--say, a supply of money determined by demographics. I have (fully) developed such a paradigm. Some means of returning money to its source is necessary, but that is structured so as to make that supply of money self-regulating. That makes the economy itself self-regulating.

if curious: "Paradigm Shift" (here in Medium but not behind the paywall)