People who get lung cancer in the US are overwhelmingly smokers.
That is a small subset of all the US people who smoke, most who do not get lung cancer.
I wonder if this research is connected to research on how smokers were somehow covid protected.
I grew up in a household of two parents that smoked all the time. My mom was a chain smoker and my dad smoked mostly cigars. Most of my siblings and I as well began smoking in our teens but quit smoking by our late thirties or forties. You’d expect chronic lung issues to be seen across most of my parents children. But there is none.
My parents also did not have any chronic lung issues, but both had lives shortened by heart disease and hypertension.