Ageing in particular is hugely expensive (most medicine is spent on the old and the old cannot work effectively) and causes incalculably huge ammounts of suffer

Ageing in particular is hugely expensive (most medicine is spent on the old and the old cannot work effectively) and causes incalculably huge ammounts of suffering (COVID-19? War? Racist killings? Rape pandemics? Drug addiction? None cause as much suffering as ageing). Is it wrong to repair someone's heart, brain, joints, skin, bones, kidneys, liver or muscles? If not, why is it wrong to prevent them degenerating in the first place?