Bill Gates' graphic isn't compelling except in the case of some cancer and traffic accidents. Most heart disease, almost all Alzheimer's, most cancer, etc. are just various ways that old people die. You're going to have to die in some manner, so reducing Stroke deaths is just going to mean more Heart Disease deaths a few years later on a person who got to live a full life.

Traffic accidents, earlier cancers, suicides, etc. take people who had much more quality life to be lived.