I think it's a bit of an over-stretch to credit Graeber with showing how flimsy economics is as a discipline. Many economists have been pointing out the same flaws for decades, starting with Keynes. While lazy academics may still teach spreadsheet-based models that bear no resemblance to reality, many thoughtful economists are grappling with the problem of how to adapt a sterile and largely harmful subject to meet contemporary needs by refashioning it and putting it on a firmer intellectual footing - a footing based on real human behaviors rather than absurdly simple-minded abstractions. The real problem for economics over the last 75 years has been the pathetic desire of economists to mimic physicists instead of realizing that the future of economics lies elsewhere.