If the birth rate is significantly below replacement, it reduces the burden of child dependents, but the weight of the elderly eventually becomes crushing. There simply aren't enough healthcare workers in the next generation to take care of their elders.
Well, like I said, the decline in birth rate could've been managed more intelligently, so we could've avoided a situation like the kind that Japan, and most other first world nations, are now facing. That is, you have hordes of young people refusing to procreate on account of a significant lack of economic opportunities (indecent wages, ungainful employment, high cost of living, et cetera), and what was, by the way, otherwise available to previous generations. In fact, it can be argued that many of the elderly today are the ones directly responsible for the predicament they themselves are currently in. Boomers, infamous as they are, enthusiastically supported the conditions (epitomized by sorts like Ronald Reagan, whose polices essentially boiled down to "let's party hard now and fuck everyone else that comes after") which have now led to a steep decline in the birth rate and, with it, a lack of care for themselves in their old age, not to mention also creating a gaping hole that whatever future workers/taxpayers/consumers that exist won't be able to fill.
For what it's worth, I'm not saying we should all crash our populations overnight, but there does need to be a significant withdrawal from continuous growth, both in regards to our global population and our obscene consumption habits. There
could've been a clear headed attempt made at accomplishing just something like this decades ago when people like Paul Erlich were loudly sounding the alarm on it, but were then quickly dismissed/ridiculed/silenced for the sake of keeping the good times rolling for past generations which are, of course, most of today's elderly. Instead of doing it the easy way, now it's going to happen the hard way. And part of that hard way is unfortunately going to include many sectors of society not having replacement level functionality, without relying on imperfect solutions like automation and immigration. The old made their bed, now they have to lay in it. I guess they should've thought of that sooner, before they sold out the future for their own bag of proverbial silver.
You can try to replace those care workers through immigration, but as mentioned previously, those immigrants typically have larger families, who begin to consume at 'western' standards. So it effectively counteracts the drop in the native birth rate, and reduces any positive environmental impact.
Part of the withdrawal from neverending growth, would also include the withdrawal from consumption as a means to measure each nation's "success". Consumerism as a concept is something that has been force fed to the rest of the world through mass marketing and advertising for decades. The standard set by the West for the last 70 years in this regard, has simply got to be dismantled. Whether it's immigrants or domestic citizens, neither can afford to consume at such reckless levels any longer. Whether you encourage more births, or open the flood gates on immigrants, this is still one of the primary bullet wounds that is not only killing any hope for a decent future, but also this planet's very ability to sustain us at all.
But I can't really blame the Japanese for wanting to preserve their distinctive culture, or for refusing mass immigration.
Japan is a sovereign nation and, of course, if it wants to hang itself on account of its own xenophobic traditions, it can freely go ahead and do so. If you ask me, this is simply their usual self-defeating stubbornness coming through. The Japanese have always loved/preferred to shoot themselves in the foot to save face, so if they're hellbent on doing it once again, then they can have at it. As an aside, it's funny how the Ainu and Ryukyu peoples were always discriminated against as "not being
truly Japanese" by the Yamato majority, but now in the modern era with the threat of having to rely on all those nasty gaijin, suddenly the Ainu and Ryukyu are regarded as brothers in arms in the fight to keep Japan "pure".
A fitting and appropriate pic I feel, at least when it comes to describing Japan's less than wise stance here.
You may as well just encourage more native births, and you'd get the same result with less social tension.
Without a deescalation on growth, it'll make no difference. You can't have infinite growth on a finite planet. This is something that goes beyond matters of localized populations and whatever their replacement levels are. Gauging our societies based on growth, is like gauging the health of a malignant tumor at the expense of the host body, the presence of which will inevitably lead to the death of both. Having said that, the birth rate
will continue to go down nonstop, so long as there remains zero room for the young to start meaningful lives of their own. Just like the now infamous painting of Jupiter eating his own son, the old devoured the young and stole from the future so they could live high off the hog. Japan and some parts of Europe are certainly a little less guilty of this than those in the USA are, but, like it or not, the trend of grotesque unsustainability was still there and the effects of it still resound out to this day. If Japan wants more Yamato births, here's a start. Maybe don't create cultural norms where it's not unusual for people to constantly work themselves to death (karoshi), or create an entire underclass of temp workers that have no benefits and dirt level wages (freeters), and then, surprise surprise, have enormous amounts of people who recoil from the soul crushing horror of it all and drop out of everything altogether (hikikomori).
What won't solve anything - War. Even if 1 billion people died, that would only be a drop in the bucket. Disease - again 1-2 billion deaths won't make a big difference. You would need to eliminate 5billion + people to have a measurable impact on the survivors quality of life for any appreciable amount of time.
I don't necessarily disagree with you, but the "four horsemen", as it were, haven't even gotten started yet. War, famine, disease, and death, will stampede across much of the human species. I'm annoyed by when my mother will sometimes say that a war, or a disease will help to curb the global population, mostly because, as you said, the total casualties are often only a drop in the bucket. However, with the advent of climate chaos and mass swathes of the planet swiftly becoming uninhabitable (such as low sea level countries like Bangladesh, or heat stroke likely zones which constitute much of North Africa), it's safe to say that there will be billions dead following the wake of such seismic changes. Lack of food, lack of living space, refugees movements that will number in the hundreds of millions. New devastating wars are coming, new plagues are coming, new famines are coming, new mass genocides are coming. Regardless of whether you believe they'll change anything or not, their happening is still a certainty.
By the way, I highly doubt the global population will ever reach 10-12 billion people. We're going to crash and wipe ourselves out long before that happens. It'll honestly be nothing short of a miracle if organized society is even still around 10 years from now.
