The recent euphoria surrounding the artificial intelligence mega-boom has led to massive concentration in the U.S. stock market, prompting fears of a catastrophic crash similar to the 2001 dotcom bust or the 2008 financial crisis. Many of these views have been aired recently on Scott Galloway and Ed Elson’s financial podcast, Prof G Markets, including a bearish stance from longtime bull NYU Stern finance professor Aswath Damodaran, who said the market was failing to price in a “potentially catastrophic” scenario.

However, one of Wall Street’s most experienced strategists has suggested that while a major selloff is inevitable, the risk to diversified retirement accounts is far more contained. Michael Cembalest, chairman of market and investment strategy for J.P. Morgan Asset and Wealth Management, explained his measured view to Galloway and Elson, acknowledging the current market’s extraordinary valuations while expressing skepticism about a catastrophic 40% drop.

Cembalest referred to the financial figure known as “Dr. Doom” to summon up a picture of stock-market bears issuing warnings when the market begins to correct: “As soon as any asset falls by 10%, Nouriel Roubini and the rest of the [bearish] people come out of the woodwork and say, ‘Okay, this is it, this is the big one. Everything’s going to go down from here.’”