How would a power structure stay entrenched like that if there's no risk of just riding it out though? If anything the apathy of today is based on the assumption that you can just wait out he current unfavorable leaders and hope you'll get better ones.

When the promise is "nothing ever changes unless you change it", then your motivations will change pretty substantially.

One practical problem is that rollout of anti-senescence will not be evenly distributed. In the early days of its availability, the oligarchs will use it to accelerate the growing chasm between the haves and have-nots, aiming to make their advantage permanent by pulling up the ladder behind them.

It's not just about power structure: if you never known anything but pharaohs and pyramids your whole life, it's extremely hard to imagine anything else. The youth is programmed to revolt against the old ideas to test them, no youth no revolt.

I also you think both your assumption and the reasoning behind it are wrong. Humanity as a whole is the opposite of apathetic, it's boiling with life. There are occasional pockets of apathy here and there, but they never last long.

And the reason why people on average are active and risk-taking is because their life is worth nothing. You lose your life no matter what you do, so you can as well do something good. And if you want to see change in your lifetime you better hurry up.

No one would risk their precious eternal lives if aging is gone. And if you want change you can safely wait forever without taking risks, maybe a meteor will fall in 10000 years and change things — who knows!

I'm mostly wondering how would compound interest work if we'd live forever.

Likely: taxation. And probably not waiting for a taxable event either. Otherwise what's to stop the bezos and musk's of the future generation locking up a significant portion of the world's wealth and hoping on a relativistic ship for 100-200 years?

That's why life extension has to come with health span extension and ways of resetting neuroplasticity. Otherwise life extension leads to a super-gerontocracy that would be hyperconservative and extremely risk and change averse.

Yeah, but if you want to reset both the body and the mind then it's not clear to me how is it better than just having kids. Nature already solved that for us and it's extremely efficient.