If you cut and paste the comment you are replying to into ddg/google you literally get hundreds of references. It’s a very well known phenomenon linked especially to increased obesity.
That article starts off with interesting science (T dropping 50% in a century, T possibly boosted for a generation by cigarettes, etc) and then takes a weird turn at Tyler Cowen and meanders into speculative woods.
Do you have a source for 'cigarettes boost T'? Is it the nicotine or some other chemical in cigarettes?
Not the best immediate source, but it identifies a study which you can look up if this isn't satisfactory: