Aging is either a disease in which case it's never "healthy" or it's not a disease. In my personal opinion aging is a disease which specifically robs an individual of good health over the passage of time. So the phrase "healthy aging" creates a deathist frame which promotes the idea that aging is not a disease. If there is a "healthy aging" then what is "unhealthy aging"?
All aging is unhealthy and if aging could be slowed, suspended, or if we develop technology to become ageless, then we would be able to maintain our health indefinitely. Indefinite health and lifespan in my opinion should be one of the primary goals of modern medicine. Preventing aging and disease in my opinion should be a goal.