The "poorest" people are not those with low incomes but rather those with low human capital endowments. That includes the elderly because, even if they are very talented, on average they will die sooner. A typical 23-year-old lower-middle-class immigrant has a higher real endowment than does Warren Buffett.
Through Medicare, the U.S. government subsidizes the health care of the elderly. Given the embedded incentives in the system, the subsidy is especially large for people in the last year of life or so, namely the very poorest.
Western European welfare states may be more efficient, because they do more to expand routine health care access for the relatively young and this may have a higher rate of return. But those same systems are in critical regards less egalitarian. Bravo to them.
Many people do not look at the contrast this way. They wish to think they believe in egalitarianism, they wish to be skeptical of the United States, they wish to condemn the U.S. for its inequality, and they wish to raise the relative status of people who are not very successful under capitalism. When you put all those wishes together, those people will be deeply allergic to my argument.
A few of these people also confuse "high social status" with "well off." Since old, high-bank-account white males have lots of social status and power, these onlookers cannot bring themselves to regard those males as holding very poor overall endowments. They substitute in assessments of social status for assessments of absolute endowments (another sign of the claim that "politics is not about policy" but rather it is about whom we should admire and condemn).
I am amazed (but not surprised) by how frequently people think of egalitarianism in terms of social markers of status rather than actual forward-looking endowments.
It is common for more egalitarian policies to be less efficient.
From the comments: "Let us say you are a twenty three year old immigrant living in New York. Would you want to trade places with Warren Buffett?
My answer is this- you couldn't pay me enough to make the trade."