For me, quitting smoking was easier than quitting coffee addiction. Coffee is everywhere, cheap, and consumption is all but encouraged. If I were to smoke I take on all sorts of baggage. Much of smoking is about being a smoker which is a mindset and community that is hard to leave. Social effects can be much stronger than physical dependence.
Operative phrase here: "for you".
As a substance its no where near as addicting as heroin, no one would actually ruin their lives for nicotine in case it was illegal and expensive.
a) The downsides to smoking are far longer term and harder to feel daily
b) You're surrounded by smokers, you can literally smell them smoking just by walking down the street
c) Smoking is legal. You can just go buy a pack.
I am unsurprised that quitting smoking is harder for some people, given that. But in terms of withdrawal symptoms, that's where I think heroin is probably worse. But I also don't really know. So far someone linked a Google search and an irrelevant paper.
There's evidence for this, too -- he quit using heroin decades ago, but only managed to quit smoking a few years back.
So it seems to be true, at least for him.