Economist Ed Yardeni has posited that a significant financial downturn, comparable to the 2008 Lehman Brothers collapse, would be required to align with the current level of market pessimism. According to Yardeni's assessment, the prevailing negativity in the market is not supported by the current economic conditions, which do not indicate a downturn of such magnitude. Yardeni's observation highlights the disparity between market sentiment and the actual state of the economy.