I'm not sure that's true? The stock market is up quite a bit if you look back a few years. Your average boglehead-style buy-and-hold investor has probably done very well.
Overall the market will win, but volatility around retirement is the issue.
EDIT TO ADD: Sincerely, thank you for your comment (and the replies providing additional context). It's given me some much needed information to go research (ala Boglehead investing).
John C. Bogle founded Vanguard, which had the first index funds. Simply put, "Boglehead" refers to someone who invests in index fund(s) and leaves the money there long-term, without trying to time the market, buy individual stocks, etc.
It's not.
The elite are largely shielded from the volatility of the masses.
It's the "middle class" whose retirement, pensions and life savings are tied up in the market that end up getting hit the most.