Similarly to the claim of materialism being unable to support meaning, so too a finite existence is claimed as lacking this. Without eternal life, it has been said, there is no point. Everything we are will one day vanish at death, and eventually not even memory or relics of what has been made remain.
To begin with, it seems more than a bit much for anyone of us to expect an eternal life for ourselves, or that our works will last forever. All things we see decay and disappear in time. Why should we find ourselves an exception?
Even apart from that, however, this claim that a finite existence is pointless strikes me as very odd. To take an analogy, does the fact that a play which moves people, stirring up heights of emotion, become pointless by the fact that it inevitably ends? I don't see how. Nor has anyone explained why this should be the case that I've ever seen.
In fact, if anything the opposite seems to be true. Something lasting forever could be very bad. This is something that has been shown in many fictional depictions of immortals. They may become utterly bored by this existence, as eventually every experience has been had. Life can become a burden even to mortals. How much more could it be for those that never die?
It is true of course that existence can be very painful, and people fail to find happiness or suffer from wrongs in this life that seem clearly quite unjust. However, eternal life, whether of reward or punishment as is taught by most religions, does not seem proportionate with our mortal existence. If our life here is finite, any eternal reward or punishment is more than any deserves.
The very notion of any eternal reward or punishment is problematic when scrutinized. No matter how inventive people get in imagining heavens or hells, at some point every possible reward or punishment will be done. Some are far more simple, as the Bible portrays it, either praising God or burning eternally. Both of those things seem rather pointless.
How can we appreciate something that has no end in our experience? Even in this life, it is far too easy to take things for granted. Imagine how then it would become if immortal, until as posited above we are bored to death. An eternal joy or suffering can only be a mindless state over time.
Even an artificial immortality as some believe science promises also seems doubtful. How is any mind capable of holding the memories which would be stored up so long a time? A mind enhanced enough to overcome this would probably leave us so changed we are no longer ourselves. In any case, all the problems with boredom remain.
So, it appears that eternal life would itself be pointless in the end.