You have it exactly backwards. The coming reduction in human population is the brightest prospect in our future. Talk of underfunded retirement plans just shows an economic/political challenge that will require much rethinking of our currently unsustainable levels of wealth inequality. As a nation we are unimaginably wealthy, we just allow orders of magnitude TOO MUCH of that wealth to accumulate in orders of magnitude TOO FEW hands. At current levels of consumption and sustainability we are already grossly over populated and the fossil fuel leveraged (expanded) carrying capacity of our natural systems is headed for catastrophic collapse.

Quality of GDP is actually more important than quantity of GDP. As the Covid lockdowns demonstrated, as a nation we have a huge and often unmet hunger for outdoor, natural experiences, for more time at home and more quality human interactions, and much less hustling just to get the money to procure and consume superfluous products. An ever expanding population and GDP is a cancer on the nation, a cancer on the globe, and for the most part, cancer kills.