We put up with automobile deaths because we get a far, far, greater benefit from having them in our society than banning them and going without.
Firearms only exist as they do because of the 2nd Amendment and the utter and complete difficulty that makes in slapping heavy restrictions or bans on them. At the same time, firearms do have useful and productive purposes such as for hunting, self-protection, or law enforcement.
Drugs, like fentanyl, on the other hand have no useful purpose. Banning such a substance is a net boon to society. We accept the use of alcohol only because of its long history within society. Fentanyl has no such history. Like opiates, heron, and other hard drugs, history shows there is a benefit to society in eliminating rather than tolerating them.