[onetwofiveten]

It's perfectly possible to learn to change your ideas and continue to learn and adapt over time well into adulthood. Not everyone does it, but I pursue personal growth and learning, and consequentially change quite a lot from year to year. I would happily commit to change and adaptation in order to live for thousands of years. I don't think I need death to give me urgency. If anything, thinking about my mortality tends to reduce my motivation.

I find the idea that an infinite living "me" would not be "me" very strange. It's like saying that if you keep adding fuel to a fire, once the original fuel has burned away it's no longer the same fire. My mind is a dynamic process, even if it changes state, it's still a continuation of the same process.

Ultimately, the ideas and urgency of ordinary human beings probably won't determine what happens to humanity in the long run. We're on course to develop powerful AI even with the technology and ideas we already have. Who knows what will happen then, but I think a stagnated immortal human race is a very unlikely outcome.