Gamnait Absolutly fantastic question!
The answer is it is a risk/(cost)/benefit analysis, like everything in life. Wearing seatbelts has zero cost, minimal risk and tremendous benefit. Without question not wearing one while driving is putting yourseldf in sakana (even though they didnt exist in chazals time(!)).
For someone prone to allergies not carriyn around an epi pen is s sakana (it has minimal cost/minimal risk and tremendous benefit) HOWEVER for everybody to carry an epi pen has Tremendous cost/ moderate risk/ and Miniaml Benefit thus it is not reccomended.
As for AED’s in those predisposed to arythmia they get an implantable device it has moderate cost/moderate risk/tremondous benefit. For the public, who are not at risk AT THIS POINT it has Tremendous cost/Moderate risk/ and moderate-minimal benefit.
As for smoke detecotrs well the cost is miniaml risk is zero and benefit, well last week’s event should be a wake up.
hope this helps
(note: my stratifying of risk/cost/benefit is complete quess work, I’d be happy to reevaluate any of them)