This is talking about people living on less than $2/day cash income. Which is still quite different from trying to get all needs with $2 cash each day, something that is more or less impossible in the US today. Those without cash live on hand-outs, soup kitchens and government assistance.
Certainly, US poverty has gotten worse over the last twenty years and is a serious problem, of course. But it seems like the focus on $2/day in particular fails to see poverty in any holistic sense.
Counter point from the Guardian on the whole Gates approach: "Bill Gates says poverty is decreasing. He couldn’t be more wrong"