Look - Henry George spawned a wave of populist reform. Mark overturned the course of history, and then Keynes dictated the policies of 2 generations of politicians across the globe. At that point, anyone with half a brain noticed that economic arguments carry immense political weight, and that this weight need not derive from underlying correctness of any given theorem.

Given this obvious insight, people with both an entirely intact brain, and quite considerable funds have made it their buisness to buy out economics.
This is not a secret.
The foundations and individuals doing this have webpages and disclosure lists.

And economics is not Physics. If you propose a theory which is in grave error, but which is pleasing to people who endow university chairs, lab experiment will not demonstrate your foolishness. Instead, the error gets perpetrated on the lives of millions, at a cost that makes all the colliders of the world seem very cheap.

Whenever you hear an economic argument look for the paymaster, and assume that you are being lied to. I would suggest that since Keynes seems to have been effective until the oil crisis, we ought to substitute away from oil by brute engineering force, and then try his policies again, because all economic thinking since his is drawn from a poisoned well.