Earlier quoted context omitted.
Really inhaling something burning is bad. Pretty much every other form of tobacco that is not cigarettes is less bad.
Chewing tobacco causes mouth cancer. Nicotine is okay, everything else in the tobacco leaf no so much.
The function of if tobacco causes cancer has as much to do with processing (it used to be cured by wood fire at a higher temperature which is where much of the carcinogenic properties came from) and the byproducts that processing creates, particularly Nitrosamine, its now cured differently in a process which is closer to snus, and somewhat safer.
Nicotine addiction (which I have) should be about harm reduction first, cigarettes are the only product that I can think of if used as commonly used will kill you or dramatically shorten your life, and it probably wont be cancer, it’ll be COPD, heart disease, or other cardiovascular issues - which are the same issues firefighters get from repeated smoke exposure. Breathing the byproducts of combustion is what’s really awful (and deadly).