From "external influences": We explore three main potential sources of positive external health effects from recessions suggested by prior literature: reductions in the spread of infectious disease (Adda 2016), increases in the quality of healthcare (Stevens et al. 2015), and reductions in pollution (Chay and Greenstone 2003; Heutel and Ruhm 2016). We find little support for a role for the first two classes of external effects, but evidence consistent with a quantitatively important role for recession-induced reductions in air pollution in explaining about 40 percent of the recession-induced mortality declines.
They don't cover lower driving (fewer accidents), health care tied to employment (under reported health incidents), or work place accidents (deaths due to statistical risk in higher risk jobs like construction, mining, etc.)
So no, not a particularly insightful study in my opinion.
[1] https://www.aeaweb.org/conference/2024/program/paper/TEE9A8Q...