Smoking has been proven to increase blood pressure and constrict blood vessels including the ones in the penis. A reduction of blood flow to the penis will prevent a man from getting hard and may even reduce sensitivity in the penis. Less sensitivity and reduction of blood flow due to smoking can be enough to cause chronic ED issues.
It’s true that great sex happens spontaneously but does not mean the sex needs to be spontaneous too. In other words any kind of sex can turn into great sex even if it’s planned because the spontaneous intangibles that turns a sex encounter from “meh” to “oh yea” happens during the sex. We are not in control of those things, they just happen, but what we can do is utilize our spirituality.