About 2/3rds of all deaths on earth is due to aging. That's about 100000 ppl daily. If aging is defeated about 50000 ppl will still die each day
Without death the world will become overpopulated and the resources that we need to survive will become depleted. Aging and death is an important/essential part of life.
If there was 1 trillion people on earth then the entire world would be like Shanghai China. People bumping into people lol we would all be living in tiny boxes stacked on more boxes