[cylinder]

Or maybe they figured out that relying on population growth to drive the economy is a Ponzi scheme. Eventually you can't add more population so you have to reckon with aging one day, might as well solve the problem ASAP. Automation combined with exports allows you to grow your economy without adding humans.

If they still wanted to, they could turn on the migration spigot at anytime. Plenty of brilliant engineers and scientists to pick off out of Eastern Europe, Iran, etc. Labor has already come in on its own.