Americans are not quite as psycho and as selfish as we seem outwardly
I would argue that there has been a shift to exactly that, and it's tied to everything happening alongside for-profit health care. America has a fetish for "self reliance" that has IMO been corrupted into "You're on your own, sucker. Got mine." instead of the ability to build a life from the land, which is likely part of the reason self-reliance ever became so important. Self-reliance also gets pushed by those who have the luxury to say it, already safe in some kind of wealth, or at least to those they look down on who have a hard time rising even to a modest level of financial self actualization. Self-reliance is pretty much the same as "picking oneself up by his/her bootstraps" these days.
The grind of the Capitalist Machine gets worse every year with the never-ending pressure to make the quarterly report better and more profitable, infinitely. That improvement comes at the cost of, well...ever increasing costs, more expensive benefits like healthcare, and having to work more for less buying power. All that on top of the fact that one bad event in one's life could send you into poverty because that self reliance twisted into bootstraps has dictated slashing taxes, and slashing those taxes has had a focus on destroying social programs that help people not be so poor, because it's your fault if you're not self-reliant, and people have decided that it's better to hoard what they can, particularly their money, and blame others for being have-nots. Why should I help some lazy (fill in the blank) when I have (insert difficulty here)?