This whole article rests on the premise "The longer you play the long game, the easier it is to play and the greater the rewards."

This is a version of the "time diversification fallacy" in finance.

The debate over time diversification has been longrunning and remains unresolved. However, there is little empirical evidence to support the claim that time moderates the risks inherent in risky assets. In actuality, a longer investment horizon increases the magnitude of potential outcomes, both negative and positive. That being said, other factors may warrant the consideration of an investment time horizon in the asset-allocation process. [1]

Also, the article suggests "doing what everyone else is doing pretty much ensures that you’re going to be average." Math check. In the case of the stock market, the "average" return of the S&P 500 index outperforms 95% of active managers' returns. Turns out ensembling informed opinions is a pretty powerful tool. Who would have thought?

[1] conclusion of https://www.vanguard.com/pdf/icrtd.pdf?2210045172