To prepare for retirement, you have two options: 1. Have children and treat them well. 2. Save and invest, so capital is available for the few children of the

To prepare for retirement, you have two options: 1. Have children and treat them well. 2. Save and invest, so capital is available for the few children of the next generation to work with. As long as millennials are doing option 2. there isn't a problem. If they rely on the pension system, then that would be a problem.