You wouldn’t be able to start a video like that 10+ years ago, now though everyone knows smoking is bad for you. Even smokers know it, it’s probably one of the most prevalent addictions. People wouldn’t still be doing it after all this time and backlash if it didn’t at least feel good.
That’s the point they are making, smoking fucks up your natural balance by making you feel good, making you crave more and deteriorating your body in the process.