Adaptists over Stasists
Even if the Castro argument is stronger than the "unnatural" argument bruited by Kass, it's not dispositive. Projuvenation technology also gives the humans under dictators stronger reasons to risk their lives to change their lives -- you can stand that boot for a while, for a lifetime, even, but could you stand it forever? And escape velocity does mean you'd be young forever, forever letting that dictator tell you how to live your life. That's a pretty powerful incentive to join a revolution, even if there's a chance you might have to give your life in exchange for freedom.
Now, tenured professors, on the other hand, might just be dispositive, but we'll take that up with another post.