Different responses to the COIVD shutdowns. The US government gave stimulus money directly to the people, for many bringing an increase to one's income during that period. The European response was focused more on helping people keep their jobs so their incomes remained stable.
Extremely doubtful that the stimmy was enough to meaningfully reduce the real poverty level. The people who already live paycheck to paycheck spent that almost as soon as they got it (hopefully on something that meaningfully improved their lives, like deferred car or home repairs, but if we're being real a lot of people blew it on gambling apps.)