There’s actually some data on this, and short answer is that immortal dictators would only last an average of 4 more years, because death isn’t usually the bottleneck for dictator survival:
The difference between leaders in dictatorships and in democracies isn’t so much in the average time they rule, but in the variability in the time they rule. Yes, not ageing wouldn’t help someone like Bachir Gemayel who was assassinated after two weeks in office, but it would probably have helped a leader like Stalin. So I care more about the variability of how much no-ageing would help dictators than the average. But still, I agree ageing isn’t the main bottleneck on dictatorship.
There’s actually some data on this, and short answer is that immortal dictators would only last an average of 4 more years, because death isn’t usually the bottleneck for dictator survival:
https://forum.effectivealtruism.org/posts/P9WGcRRa2cfAGeRvT/against-immortality#GPKWcB5xenEhRBtRk
The difference between leaders in dictatorships and in democracies isn’t so much in the average time they rule, but in the variability in the time they rule. Yes, not ageing wouldn’t help someone like Bachir Gemayel who was assassinated after two weeks in office, but it would probably have helped a leader like Stalin. So I care more about the variability of how much no-ageing would help dictators than the average. But still, I agree ageing isn’t the main bottleneck on dictatorship.