In my case, I don't think lower nicotine would have increased my smoking because I believe it was the act of smoking I was addicted to, not the drug. I'm sure nicotine had some effect on my quitting, I doubt I'm a special snowflake, immune to the addictive qualities of a substance. However, if nicotine is the only reason someone smokes, they're going to smoke whatever it takes to get their fix. Even without nicotine, the act of smoking anything is harmful. The more of that they do, the worse off their lungs will be. If anything, I think more nicotine per cigarette would be better.
It is like saying that if people need X amount of calories and you decide to put them on a diet by just giving them smaller portions, they will simply eat more portions to hit the calorie level they need.
If they smoke for the nicotine, they will smoke until they get the amount they crave. If they smoke because they like something else about it, then they won't. But most people smoke for the nicotine, or they would have some other habit instead.
People are used to a given amount of nicotine. If each unit of tobacco product has less nicotine, they will consume more units to achieve the amount of nicotine they are used to.
