There are a couple more charts in that vein at one of the pages the post links to: https://ourworldindata.org/life-expectancy#it-is-not-only-ab...

If you look at life expectancy difference for teens and young adults, seems like the main difference between the 1800s and today is that instead of dying at your late 40s/50s you die in your 70s/80s, which is very intuitive to me at least. This is when regular visits to the doctor become important. I wouldn't be surprised if heart issues alone is the main driver of this trend.

Even life expectancy at age 25 is mostly meaningless, actually. Women mortality (due to childbirth) took a significant toll on the average life expectancy as well. And another two significant scourges were famines and epidemics.

Well, if you take away all the mortality causes of the time you'll end up thinking things were pretty good back then, since people weren't dying in car crashes.

Yep, but life expectancy is not a very intuitive concept. When they read "life expectancy was 25 years", many people tend to think a 30 year old was some kind of lucky but senile guy back then. Dying of old age was just not the norm.

Dying of old age was a norm. There were plenty of old people way back when. It's just that lots of people dying young (well across all age groups) was the norm too.

Actually women delivery mortality became horribly bad with the invention of maternity hospitals and before the invention of sanitation.