My dad is 98. Started smoking when he was 9. At one point he was smoking 70 a day. He worked as a fireman on steam trains when he was in his 20s. He lived in London during the 1950s when the smog was so bad you could walk into a lamp post when the lamp above was lit. People warned their houses with coal, powered the city with coal, burnt their trash in the back garden and smoked a lot. Sure, the average lifespan was low. But he only quit smoking in the 1980s. I'm not saying that smoking isn't bad, but if there is a sudden rise in cancer among young people, it's not that simple. The number of smokers today is tiny. In the UK, smoking rates among young adults (aged 18-24) have significantly declined over the last few decades. In 2011, about 25.7% of this age group smoked, but by 2021, that number had fallen to 13.2%. I don't have stats from the 50s but according to my father he didn't know anyone who didn't smoke.