I get the feeling that inflammation, especially chronic inflammation, is terribly overlooked as a risk factor.

And "what doesn't kill you makes you stronger" is a terribly inaccurate turn of phrase that unfortunately informs many people's thinking, especially when it comes to unpleasant activities like getting regular vaccinations.

There's a lot of research in this area :) May I introduce you to the term "inflammageing"...

https://pmc.ncbi.nlm.nih.gov/articles/PMC6146930/