LU:
Your statement is totally false. I am impressed with the logic pattern here. First, one declares a position, then one looks to find a way to justify it. That is backwards thinking.
I have posted on other threads here on this, and won’t repeat myself. There is an extremely long list of universally recognized poskim from the present and previous generations that openly wrote that smoking is an issur d”Oraysa. There are a few seforim dedicated to the subject, and present all the information, with detail and precise references.
No, Gedolim do not need to tell us that chazzer is forbidden. The Torah does that. If we have a question, related here to the health risks, that shailoh is decided by the scientific experts. The purpose of Gedolim weighing in on it is because there are many who wish a different psak, and will challenge the scientific findings. We all know that to be either primitive or plainly stupid, but that is the logic I referred to at the beginning, where the arrow is shot, then the target painted around it. Enough Gedolim have issued their clear, definitive psak, so no one should be left with a question.
Telling us that a talmid chochom smokes does not impress me at all. It does not pasken a shailoh. It just attests to an addiction which that individual cannot overcome. I cannot declare him to be a baal aveiroh, just a choleh. Like I would not mimic going for surgery or medical care because a talmid chochom did, because I don’t need it, I will not accept that his smoking does anything to change halacha.
Lastly, a research finding indicated that smokers had a lower incidence of Alzheimers Disease. Preparing to fund massive research, the discovery was made that smokers tended to die of other illnesses long before there was a chance for AD to set in. To consider smoking muttar is simply foolish, and clearly against halacha.