nothing you said changes the incentives in front of researchers. Grant money is there in the billions for cancer research, obesity research etc. There is essentially no grant money there for basic longevity research. I say this having spoken with people trying to get funding for basic longevity research.
Maybe there's just less longevity researchers. The absolute funding makes little difference from an individual career perspective–even if it does have a large effect on the field as a whole.
I've linked to a page of academics from top institutions[0]. If you're at Harvard researching longevity, then you're doing OK career-wise, imho.
If you sell your company for $720 million, you're doing OK career-wise, imo.
Novartis[1], the pharmaceutical company, who ranked number one in world-wide sales in 2013 is working on a longevity drug based on rapamycin.
Elizabeth Blackburn got a Nobel Prize in Physiology or Medicine, in 2009, for her work on telomeres!
Quite frankly: lulz!
[0] http://www.elysiumhealth.com/team [1] http://en.wikipedia.org/wiki/Novartis