I want to point out that the linked article is hyperbolic (as most “Japanese people aren’t having kids/sex/etc.” articles are), and its title is outright misleading.

It claims that Japan has the lowest birth rate ever. And while it may have the lowest number of births, that is to be expected in any country with a birth rate below replacement - I.e basically the entire developed world.

In fact, as opposed to the US, UK, Canada, Australia and New Zealand, Japan’s fertility rate has actually been increasing for some years now. See details here: https://fred.stlouisfed.org/series/SPDYNTFRTINJPN

I really wish this meme would die, but it obviously drives clicks so people keep publishing it.