If you smoke one or two cigarettes a day, it’s not too terrible.
The probem came from people smoking a pack a day or more, and yes, it’s the kind of habit that tends to grow.
When big tobacco made the stuff plentiful enough that people could support pack-a-day (or even case-a-day) habits, the money was just too good not to defend by surpressing science.
As the fossil fuel revelations have shown, billionaires get desperat for money, and can’t imagine deciding they have enough or sharing substantial portions of their wealth to change the world for the better.