Probably a combination of: - US letting it rip through vulnerable populations with the promise of "herd immunity" being right around the corner - Fewer hospit

Probably a combination of: - US letting it rip through vulnerable populations with the promise of "herd immunity" being right around the corner - Fewer hospital beds available in less populous areas. - Taking COVID seriously became a culture war issue. So while some countries might've had its youth catch it while mostly keeping it away from older populous, the US had the opposite: less vulnerable youth took it relatively seriously, with lots of 60+ flaunting safety measures they felt were oppressive