Yes, and there’s a clear reason why.
Smoking reduces the amount of oxygen arriving at the wound. A wound rebuilding tissue needs a blood supply carrying oxygen to it, and less oxygen arriving means less of what the repair requires.
There’s a second effect that lasts beyond healing: any scar tissue laid down when the wound heals will be of poorer quality.
Smoking also interferes with healing more generally. Diabetes, poor circulation, nerve damage, infection, immobility, poor nutrition, smoking and excess alcohol use are all factors that impede healing and can explain why some wounds do not heal.
There’s no set figure for how much slower healing is, or how soon stopping makes a difference.
If you smoke and you have a wound that is not healing, this is worth raising with the person treating it rather than leaving unsaid. It is part of the clinical picture, and the conversation is a practical one about support rather than a reprimand.