Because death is terrifying at a primal level that almost can't be articulated.

Anything that reduces the anticipated terror and misery is seen as desirable.

That's mostly what cryonics is about, by the way. It gives hope at your moment of death that perhaps you'll come back someday.

Oddly enough religion is not just about that, but it does serve that purpose often.

Because for most people involved, the tiny slice of life where you're dying is the only thing they empirically experience.

I can't parse this sentence.

I think it's a convoluted invocation of the idea that everyone is dying from the moment they are brought into this world of struggle and entropy.