I disagree that the passenger's life expectancy at birth in the country of their birth or destination country has anything to do with how an airline should handle a medical diversion. The airline is in the business of providing transportation. If diversion to the nearest suitable location for emergency medical treatment is deemed necessary, then the airline should provide transportation to that point, first aid to whatever extent they are able, and hand the case over to the local medical system. Making moral judgments about whether someone has lived quite long enough already does not enter into the equation.