Escape Velocity: Why the Prospect of Extreme Human Life Extension Matters Now

longer-lived species will show a smaller maximal proportional life-span extension in response to starvation, probably not much more than the same absolute increase seen in shorter-lived species.

We know that, at least, the benefits marginally decrease

a strategy built around the actual repair (not just retardation of accumulation) of age-related molecular and cellular damage—consisting of just seven major categories of ‘rejuvenation therapy’—that appears technically feasible and, by its nature, is indefinitely extensible to greater life spans without recourse to further conceptual breakthroughs.

This would later become the basis of the SENS Foundation

The escape velocity cusp is closer than you might guess. Since we are already so long lived, even a 30% increase in healthy life span will give the first beneficiaries of rejuvenation therapies another 20 years—an eternity in science—to benefit from second-generation therapies that would give another 30%, and so on ad infinitum. Thus, if first-generation rejuvenation therapies were universally available and this progress in developing rejuvenation therapy could be indefinitely maintained, these advances would put us beyond AEV.

This is a hard to grasp concept but a game-changing one

We will probably not have effective rejuvenation therapies for humans for at least 25 years, and it could certainly be 100 years.

And yet 13 years later some of these therapies are already in clinical trials

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC423155/

(not my pic)