Most of the improvements are invisible. Better crumbing zones, better shock absorption, better composite materials. If you watch crash test of a modern car Vs 10-y old car, the later is significantly more dangerous. 20+ year old? Basically a death trap.
Those numbers include pedestrian deaths, which the same wiki article states "began rising in 2010, and exceeded 6,000 by 2018" (constituting a higher percentage of deaths in 2018 than in 2010).
If you subtract off the 6400 pedestrian deaths in 2018 and the 4200 in 2010, then you do see a drop-off in fatalities per hundred million miles driven -- from 0.971 in 2010 to 0.935 in 2018 (and even lower in 2019 at 0.925, as the raw number of deaths went down as miles traveled went up).
(Further, this isn't even considering other non-automobile occupants in crashes, whether that's bicycles or motorcycles.)
