I am not sure I would trade our "problems" for Japan's, or virtually any other country's. Japan is demographically old, and needed robots early on. Its low unemployment rate is more the result of having very low birth rates for decades now. Demographically, Japan is screwed.
It is also a country heavily in debt (highest debt to GDP ratio in the world) with per capital share of the national debt nearing $100k EACH. The currency is propped up by the state banks, which are tightly controlled by the government. Monetarily, Japan has major issues.
More subjectively, its virtually homogeneous society has resulted in (by some measures) a closed culture. Japan is not an entirely pleasant place to live for a non- Japanese/ non-native- never personally lived there but world traveled execs I know label it the most racist culture they have experienced, especially toward fellow Asians.