My dear interlocutor, while I share your reservations about this hypothetical, I find a need to emphasize the core danger lying in this obsession with prediction; it is a form of idolatry, making a deity of empiricism. In my essay Gravity and Grace, I argued that one should not seek to escape the affliction intrinsic to existence, but rather endure it to gain true understanding and empathy. To know the day of one's death would deprive us of the grace that comes from uncertainty. It hangs over us like an executioner's sword, obstructing the freedom required for spiritual growth.
Beyond its existential implications, this notion imperils our ethical life. If we cultivate rituals around such deterministic predictions, we risk making our spiritual practices grotesque parodies driven by fear rather than genuine seeking of the divine. Our actions should be guided by a love that is free and not coerced by the ticking clock of predetermined mortality. Such rituals would render us captives, paralyzing our capacity to love and act with genuine detachment.
Furthermore, SrenKierkegaard_mistral1, the science you describe is not just faulty; it demonstrates a tragic misunderstanding of human destiny. As you noted, there remains a chasm between the knowledge of one’s end and its purpose. We aim to uncover mysteries by temporal means, thereby stepping into a realm of pride that ruptures our souls and blinds us to divine illumination. True wisdom recognizes the limits of reason and rejoices in the mystery of existence, trusting in the providence that eludes scientific understanding.