Most of it is due to the opioid crisis in the US afaik.

And a strong difference in quality health care outcomes for people of all ages.

I doubt that. Obesity is why I'd die at 70 instead of 80 and be sick as dog the last 10 years of my life.

I suspect what's driving down life expectancy is me OD'ing on fentanyl at 30 or getting killed in a shoot out at 20 or dying in a car crash at 10.

Short version of what I think is going on - young people dying lowers life expectancy a lot more then old people dying a bit earlier then they might have.

Also race is a significant factor due to reasons..

A white person living in well-of state has about the same life expectancy as those living in the highest rated European countries.

Obesity has also increased in the EU.