Sooo... because a number of Americans don’t have a 401(k), I should stop contributing to mine? What kind of garbage is this?
Your employer does not have to offer a 401(k)/Roth plan for you to invest in one.
And, I'd add that at half of the places I've worked, the fund offerings have been sub-par (2+% fees on a 500 index? Please.). I just contributed enough to get the match, or hide what needed to be hidden from taxes.
Some employers did well, some not. However, I like *all* of the investments that I make on my own. (they're not all good, but I don't need to 'settle' when I make them....)