When there's a dictator or other unjust rule, the one thing you know that will end that rule is death. That not happening would change things incredibly. Imagine if the same old politicians of 1950 were still in power, we'd still be trying to pass desegregation. Death of the older generation allows new ideas to flourish. I feel sorry for the children of the first generation to avoid death(if it could even happen)
Science advances one funeral at a time. - Max Planck, paraphrased.
So does culture, for that matter.
I wonder what impact it will have if/when people do start living for 300 years or more (which some people claim we could see within our lifetime). What happens when racist, openly homophobic grandpa isn't just someone you uncomfortably bear and forgive, but someone with a lot of power and money because they've been around the longest? Investments, compound interests, connections, so many things that would mean that the younger generation would have less and less power and hope as time goes by.