If you want a grim take on this looking into the quantum immortality thought experiment. I can't remember who wrote it, I think maybe Chalmers, but the idea is

If you want a grim take on this looking into the quantum immortality thought experiment. I can't remember who wrote it, I think maybe Chalmers, but the idea is that while the experiencer is immortal, they will still accumulate injuries, old age, etc. It would not be a very pleasant immortality.