There was an episode of Sliders where you can withdraw however much money you want from an ATM, but each dollar is a ticket in a euthanasia raffle to keep overpopulation down. A little different from micromorts though.
There's got to be some more formal line of research or thought about population management in a post-aging world.
I also question whether a mass die off event on this planet won't lock us out from ever rebuilding a spacefaring civilization. We've already used up all the readily accessible fossil fuel that was necessary for us to get this far.
But what are the alternatives if people stop dying of old age? If the birth rate is even marginally higher than the very small death rate, we eventually over populate. The only way to resolve that is some kind of culling mechanism. War, starvation, and disease are what usually happens to humanity when resources get too constrained.
But now we have nukes.