Despite having a number of vices including smoking I am not entirely against a total ban, it is though a bit nanny state approach protecting people from themselves or isolating them from society.
The future path and direction though could be a concern.
Consider a few similar potentially harmful vices, caffeine, sugar, fatty foods, alcohol, loud music, hey might as well throw religion in there so lets say we ban them all.
Without vices is it really beneficial to society, keeping people calm, people finding a release in some way doing some things they enjoy and give them a level of pleasure, to take that all away, a lot of the things that make us who we are, would we be in a worse state, perhaps with people seeking other vices to fill the gaps.
I would never want my kid to start smoking for example so I can see why some countries are using that as a future ban based on age.
However if we go down the complete ban route then we'd need to be okay with all those other ones going shortly after and at this point its not something I'd be keen on being part of.