There's only so many countries that will have a surplus of young workers though, and arguably they're ones with cultures/ethnicities least likely to be readily

There's only so many countries that will have a surplus of young workers though, and arguably they're ones with cultures/ethnicities least likely to be readily integrated into Japanese society. And such workers are likely to have better options available as other countries with more of a history of accepting immigrants look to remedy their demographic woes. I say that as a Westerner with an ambition to spend some time living/working in Japan - but AFAIK the only way it would be possible currently is to legally marry my (Japanese) partner, so most likely we'll go elsewhere.