The Japanese economy is experiencing a prolonged period of depression, starting from the bust of the bubble economy. Some have even called the past two decades as "the lost 20 years."
Because the human brain is well developed and capable of adapting to the environment, it is possible and natural that the Japanese people are experiencing days of low key mentality. The coupling of the national economy and the sentiments of the individuals in this way, however, is certainly not something inevitable.
It is entirely possible to "decouple" one's mental activities from those of the nation. One could have one's own brain "grow" at a high rate, despite the fact that the economy in general is in stagnation.
The leaning process of the brain is open-ended, and one is certainly able to keep learning, as the study materials have become more or less free with the advent of the internet.
The single important wisdom for anyone in today's world, whether living in Japan or anywhere else, is to decouple one's learning process from the social contexts and make it grow rapidly, to achieve one's hidden potentials.