that literally IS how that works.

saying "thing x kills this many people a year and thing y kills this many" is LITERALLY how we define how "deadly" something is

plague doesn't spread person-to-person in the US because we don't live in medieval europe cities with no indoor plumbing, hand sanitizer, or rat poison. Your chances of dying from Bubonic Plague are basically zero, because you have zero chance of even catching it in the first place unless you've handled the corpse of a wild animal that was infected with it.

The only people I'm finding any information about who've died from Cannabinoid Hyperemesis Syndrome are people who were multiple time a day weed smokers for a period of longer than a year.

So if you smoke weed once a week you've got about the same chance of dying from it as you do of being struck by lightning while sitting indoors on a sunny day.