The benchmark is people such as yourself bleating about nicotine and ignoring the other factors.
If nicotine is the addictive element as you assert, why do around 50% of addiction-positive blind test subjects exhibit addiction to the placebos? There's no nicotine (or indeed any other particularly addictive substance, like caffeine or sugar) in them, yet they still return addictive results...
If nicotine is the addictive factor, why do so many nicotine-centric alternatives fail to get people off the smokes? If nicotine were all it took, NRTs would be 100% effective.
There are other factors and contributors at play, of which nicotine is only one and not even the main.
For example, you also said "People don't just smoke because it is "pleasant" (as it is distinctly unpleasant)" - Some people actually do, though which aspects they individually find pleasant is subjective. Some get into cigars or pipes because of the smells. There are also people who were non-smokers, yet took up vaping using liquids with no nicotine content.
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