The quoted excerpt is referring to only the subset who has maxed out their 401k contributions, whereas you're describing the median, who mostly have not. These

The quoted excerpt is referring to only the subset who has maxed out their 401k contributions, whereas you're describing the median, who mostly have not. These are different groups. People who maxed out their 401ks for their working years and had vaguely reasonable investment options (mostly diversified stock funds) will be fine. And social security income should not be ignored.