One of the neat thing about sens research is that if you happen to even get one or two of the parts of damage fixable or even moderated, then you have a much less inactive old age period, even if no actual longevity is gained.
I find decrepit old age to be one of the biggest issues of our time (who cares if grandma is 80 if she can move like she's 50; the issue society faces today with the elderly is one of them not being able to take care of themselves).
Additionally, with the aging of Europe and Japan, prolonging the useful life of the workforce is a big worry.