Comment by NoMoreNicksLeft

> I think many people have a misunderstanding of what lower fertility means. Imagine a country has a fertility rate of 1. It doesn't seem that bad because it's pretty close to replacement.

That's not even close to replacement. It's somewhere above 2 (often cited as 2.1, but it may be more like 2.04 in times of peace) for it to be replacement. If you could magically make fertility be that number, population increases would only come as a matter of life expectancy increase.

1 actually implies some sort of high-speed demographic implosion that will wreck an economy within a single human lifetime.

> It's easy to imagine 'oh we'll just fix it if it becomes a serious problem like that'

If it takes 30 years to recognize the problem, then one generation has already aged out of ever possibly being able to fix the problem, and the next generation is getting too old to be able to fix it (unless you can do so instantly). You've only got a few generations at a given time that can fix it.

> Japan, for instance, hasn't even hit the worst of it yet. Their fertility plummeted about 40 years ago.

There are fewer people living in Japan today, than there were a year ago. They didn't leave to go elsewhere. They died. And it will be like that every year until there are zero Japanese left. They have been functionally extinct for a few years now, though they may not know it yet.

> it even further is indeed speedrunning the extinction of Western civilization!

There haven't been distinct, compartmentalized civilizations on Earth for over a century at this point. There's only the one civilization. And, if it dies, there likely won't be another. Who had "can't be bothered to fuck" on their Fermi's Paradox bingo card?