Where do you think this change is coming from? When I was a kid, there was a huge billboard right next to my school with a man wearing aviator glasses, an airplane in the background, smoking Memphis cigarettes. That was the coolest guy I've ever seen.
Compare that to 20 years later, there's a photo of a depressed guy on the package and a message "smoking causes infertility".
When I first started at uni, students still smoked in the auditorium. That was cool.
By the time I finished, people who smoked had to go outside and stand in smoking zones like animals. The opposite of cool.
There's a reason why the public perception changed. I don't think the public perception would have changed as drastically without government intervention.
https://news.gallup.com/poll/237908/smoking-rate-hits-new-lo...
Hell, when I was in high school, you could still smoke at 16.
I'd argue the health risks have become way more know, which drove most of the reduction.
I smoked for about 10 years between the mid 80s and 90s. When I started, most of the 'cool', 'sophisticated' etc people seemed to smoke. When I stopped, it was mostly a health choice, but partly because it seemed no longer 'cool', everyone I knew had given up or was trying to.
I can't even fathom why anyone would start smoking now, it seems like an affliction of the poor and/or the old rather than anything sophisticated.
All of this is mostly a change in fashion, people having a deeper awareness of the health risks, becoming aware of tobacco industry manipulation, etc. No doubt government messaging aided and supported that change, but it is not the only or even the main cause imho.