There are no health benefits to smoking, nor is there a "safe amount"
That’s not entirely true. Nicotine has been identified as potentially having benefits for therapeutic use in Parkinson’s, Alzheimer’s and ADHD. It’s a hard sell given the image issues but I think there’s a general recognition that in small doses nicotine isn’t actually harmful. It can be lethal in large quantities like many other substances of course.
Smoking, or inhaling anything other than air in large quantities generally is the issue. BBQ’s have been found to be pretty highly carcinogenic as has burnt food, red meats etc and it’s actually quite hard to unpick smoking related fatalities from other air pollutants given the rise in both on very similar timelines. That said, it’s quite obviously best not to deliberately directly inhale anything that is burning/highly heated so the shift against smoking can only be a good thing.
I do think there’s some cognitive dissonance going on when people try and say alcohol can be beneficial. There are very small benefits from ingesting alcohol which are achievable in other ways that don’t harm your body at all. Particularly in the UK our lifestyles and diets put a lot of strain on our heart, gut and liver so any tiny health benefit you might get from alcohol is quite quickly cancelled out by other factors. Age is one of the risk factors for fatty liver, especially in women, so it’s debatable whether any alcohol has a measurable health benefit.
Of course we enjoy alcohol so that’s a big factor in why it’s acceptable but I’m not convinced that we should be quite so keen to ignore the harm it can do because we don’t like hearing it.