It appears to be axiomatic that Japan's ageing population is necessarily "a bad thing", and that this can be tackled by immigration.
However, Japan's GDP growth is not too different from that of similar OECD countries that have much greater rates of immigration. Many European countries also have similarly ageing populations, but their more relaxed immigration rules don't seem to make a big difference to economic growth.
So if Japan's productivity is maintained, I don't really see that a falling population is a major concern. In fact, it could even conceivably have a pay-off in terms of reduced environmental burdens and cheaper housing.
However, Japan's GDP growth is not too different from that of similar OECD countries that have much greater rates of immigration. Many European countries also have similarly ageing populations, but their more relaxed immigration rules don't seem to make a big difference to economic growth.
So if Japan's productivity is maintained, I don't really see that a falling population is a major concern. In fact, it could even conceivably have a pay-off in terms of reduced environmental burdens and cheaper housing.