One can't time the market, though. Every time in the past, where I thought to myself, "I should diversify away from the US stock market," when I looked back and did the math, I would have lost more money doing that than leaving it invested. The only way I would have come out ahead was if I sold everything the exact right month in 2000, the exact right month in 2008, and the exact right month in 2020. Who knows in advance what that correct month is?
Diversification is a tool for reducing risk, and reducing risk does reduce the expected return of your portfolio. You can make money by running in front of a steamroller picking up pennies. But most people are not risk-neutral.
