Clearly we don’t have the mass disruption to social security payments, the medical industry, and to Florida real estate. Nor the mass inheritances followed by some smaller amount of mass frivolous spending. No jobs are suddenly vacant when the oldster employees fail to show up as scheduled.
So the aftermath will be simpler for all those reasons. BUT …
We still need to dispose of (WAG) a billion bodies. At least they’re smaller on average.
Kids are the other big consumers of medical care after oldsters. It’s the 13 to 69 year old group who mostly never needs a doctor. Kids also consume large amounts of tax expenditure and civic infrastructure in the form of schools. All elementary schools close tomorrow for at least 6 years, then (maybe see below) gradually refill. High schools still have pupils for a couple more years then they wind down over 4 years and stay shut down for 13 (or more see below) years before the next set of kids become freshmen. Colleges have a decade to prepare for a decade-plus drought in their main customers.
Certainly parents spend huge amounts of money on feeding, clothing, entertaining, and stimulating the little sprogs. All that economic demand will disappear at a stroke. Second-hand stores and Craigslist will be swamped with little shoes, onesies, toddler dresses, car seats, footballs (round and pointy kinds), baseball mitts, Barbies, bikes, and all the rest. For which there will be no buyers for one to 13+ years …
The long term demographic jolt will be huge.
The larger issue I suspect would be the psychosocial impact. Think of all the people who were parents yesterday and aren’t today. Oldsters want to live a long time yet, but everyone including them, knows their days are numbered and at 70-plus their fuse is short and getting more so. We mourn the death of an oldster, but we’re not surprised by it.
Dead kids are different. It’s shocking; it’s wrong; its …
How many just-were-parents would get back to making more? How soon? How many would age out of childbearing years before they were ready to try again?
Would the public at large be paralyzed by the fear the mass kill might happen again? Even if the aliens came clean about being the culprit and said it was a one time act, who’s to trust aliens who’ve already proven they’re willing to do something so heinous?