you are right for the most retirement account

In most cases, we started little or nothing in a retirement account.  DAC is very powerful in this case.  In a lot of cases, it can beat S&P.

However, when your account grows to certain level (10+ x of your annual contribution), your contribution can only buy small amount (less percentage) comparing your holdings.  Then the market up/down have huge impact on your return.  Then we need to pay attention to the market and avoid the big dip when the risk is high (like now).