Many incurable diseases come with an awful quality of life, like CF. Even cancer, treated or not, is a terrible experience. Just aging, what you call “a disease”, is nothing like that.
Aging comes with a terrible quality of life. By the end, the person is severely debilitated.
Osteoporosis can make it so that a fall can lead to major fractures, which leads to a severe reduction in a person's independence. Macular degeneration can make an elderly person blind.
Neurological deterioration can take the form of conditions like Alzheimer's, where a person loses their memory of everyone they love.
The body, as it ages, becomes much more susceptible to other, terrible, diseases as well, like cancer, heart disease, and diabetes, each carrying its own set of debilitating effects that degrade quality of life.
Alzheimer is not aging, it is a specific disease. Same as cancer. Sure, advanced age can make you more susceptible to some diseases, but aging itself is not one.
Aging eventually makes you orders of magnitude more susceptible to most major diseases, while coming with its own set of debilitating effects.
Aging is the gradual accumulation of cellular and bodily damage. Nothing would do more for human health than having effective treatments for arresting and reversing that degradation.
