We live in a world that will soon make that untrue, in the same way a ship can be replaced piece by piece over time and remain the same ship. If we moved to digital existence, we could manipulate our time perception to essentially live forever. Maybe not your generation, but your grandkids; just a few decades after we discover ASI.
Not forever. That is the self-delusion that billionaires want to believe. Basically, they see themselves as above the rest of mortals and think: and now I have to die, like the rest of the suckers living in the world? They are spending a lot of money first to extend life as long as possible, which is not bad, and then to be able to reach the transhumanism you are talking about.
But everything has an end. However much we can transfer our 'minds' to another physical medium, the possibility of a nuclear war or a cosmic cataclysm will always be there. Even the sun has a limited lifespan. What will humanity do when the sun's life is over? The nearest star is 4.3 light years away, and there are no habitable planets there.
It may be possible to extend life indefinitely, but forever, no way.