>Japan is nowhere near the most densely populated country on earth. It's the 40th. Less dense than Belgium, Israel, India, Singapore, and South Korea, just to name a few. Calling Japan cramped for space is a stretch.

But relatively little of Japan is actually livable: if you look at Honshu, most of the population is in plains on the coast, and most of the inland area mountainous and hardly inhabited.

For example, about a third of the population of Japan lives on the Kanto plain which represents just 4.5% of the land area.

Japan is also 73% mountains, so the populated areas are much denser than a simple population divided by area calculation would give.

> Japan is nowhere near the most densely populated country on earth. It's the 40th. Less dense than Belgium, Israel, India, Singapore, and South Korea, just to name a few. Calling Japan cramped for space is a stretch.

This is good rhetoric but poor logic. The mere existence of denser-populated places has no bearing on whether a particular place is too densely populated, any more than the mere existence of more polluted places has any bearing on whether a particular place is too polluted.

> Japan is also not having any kind of managed population decline, unless they choose counterbalance old people dying with immigration.

The idea that mass immigration is the only way to manage population decline is absurd and unserious.

I've only heard this through word of mouth, but I heard a theory that one of the biggest reasons for the decline is because the work culture doesn't leave much time for life outside of work, diminishing the possibility of starting new families.