Why is it an evolutionary design mistake? It's perfect from an evolutionary standpoint. They get you through sexual maturity, reproduction and plenty of time to

Why is it an evolutionary design mistake? It's perfect from an evolutionary standpoint. They get you through sexual maturity, reproduction and plenty of time to see after your offspring. What happens afterwards is bonus time on the planet, it's free-for-all everything goes wrt to your body. Evolution didn't 'design' us to last that long..