If I look around me - and I'm more at the bottom, at grassheight relative to billionaires and UHNWI in general on skyscrapers - I see a host of other immediate "longevity issues". For one there is a substantial amount of people just trying get by and being like 50/50 on the choice of rather being dead already or trying to get through somehow 'till the next day, ad infinitum: from depressives who are stuck in a loop o…
If you look 100 years back, Rockefeller was the richest man in history (and might still be...), yet 1 of his 5 children died in infancy of a bacterial disease. These days, such diseases are extremely rare for about 1bn people in the western world, all of whom are effectively wealthier than Rockefeller was.
Yes, you can "save" people from poverty by giving them money, but ultimately you're just condemning their children to the same fate (after your money runs out). The only real progress is technology. And billionaires spending on anti-aging is exactly the kind of technology that will immensely benefit billions of people in the future.