The cause was easy enough to identify: Data parsed by Kuhls and her colleagues showed that drivers were speeding more, on highways and on surface streets, and plowing through intersections with an alarming frequency. Conversely, seatbelt use was down, resulting in thousands of injuries to unrestrained drivers and passengers. After a decade of steady decline, intoxicated-driving arrests had rebounded to near historic highs.
… The relationship between car size and injury rates is still being studied, but early research on the American appetite for horizon-blotting machinery points in precisely the direction you’d expect: The bigger the vehicle, the less visibility it affords, and the more destruction it can wreak.
Per the article:
Federal stats show that seatbelt use dropped a little in 2020 and 2021 as compared with previous years, and then came back up in 2022, with a huge jump in seatbelt-non-use contributing to fatalities in 2020
More recent data isn’t available yet.
The timing coincides with COVID so I wonder if it really is the whole anti-masker “government can’t tell me what do and besides I’m immortal!” mentality.
Could be; could also be that infection alters peoples behavior.