Forced to find the courage or die trying to. And I really doubt that knowledge that their despot will eventually die has much effect on people's motivation to r

Forced to find the courage or die trying to. And I really doubt that knowledge that their despot will eventually die has much effect on people's motivation to rebel as in most cases there is a clear line of succession. In many cases there isn't even a single despot to point to. This isn't even considering how such anti-aging technology would prevent despots' mental acuity from deteriorating as they aged - in fact they would probably grow sharper as they gained more experience so to speak. And aging/succession have almost always been one of the greatest destabilizers of a successful authoritarian regime.