How is someone who claims to be known for their writings on dark markets and bitcoins supposed to be an expert on smoking? Meanwhile, actual scientists and oncology doctors have concluded that for nicotine on its own (not smoking) (https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4363846/) "There is an increased risk of cardiovascular, respiratory, gastrointestinal disorders. There is decreased immune response and it also poses ill impacts on the reproductive health. It affects the cell proliferation, oxidative stress, apoptosis, DNA mutation by various mechanisms which leads to cancer. It also affects the tumor proliferation and metastasis and causes resistance to chemo and radio therapeutic agents."
> How is someone who claims to be known for their writings on dark markets and bitcoins supposed to be an expert on smoking?
This is a non-sequitur in context: Gwern's whole thing is trying to take a from-scratch look at the literature instead of relying on the standard appeal-to-authority arguments that sometimes lead to flawed conclusions due to things like institutional incentive structures. That is to say, if you're the kind of person who reads thing blindly based on whether the author is an expert or not instead of taking advantage of the fact that he shows his work to assess the quality of his analysis, then gwern's writings probably aren't for you. (FWIW, you should probably be doing this to some degree even when reading the recommendations of those designated experts)
Don't get me wrong, there's obvious ways for "ignore the experts and read the literature from scratch" to lead to flawed conclusions, but it's just a different type of analysis.
Did you look at the page thoroughly? More citations to peer-reviewed studies on nicotine than Wikipedia. That’s what he does. And his research into the dark web and bitcoin was very thoroughly researched, analyzed, he posts his datasets and methods used to reach conclusions, etc. Are you suggesting that someone studying these has lost credibility because of the nature of the dark net and such? Or are you suggesting that a person is only capable of applying investigative and analytical skills towards only one area of study?
https://www.gwern.net/Nicotine