Unless you plan on getting killed....
Yes, this headline is rather harsh, but so is being dead. I don't mean somebody is going to attack you, but rather the silent deadly killer. Sarcopenia, the gradual loss of muscle. It will reek havoc on your entire system. Possible killers are diabetes, cancer, heart disease, falls, etc.
So unless you plan on getting killed, you better plan on getting older. Money in the bank, and muscle on the frame. Both are consequences of effective planning, and both are among the most important things you can do.
The muscle mass that is the hallmark of physical strength is the key to longevity, to health, and the maintenance of physical function.