A lower ratio of workers to seniors is supposed to be a problem because the workers need to produce stuff both for themselves and for non-workers. It's an argument that there will be too much demand, not enough supply.
If you then say that consumers aren't buying enough and there isn't enough demand, then that could also be a problem (recession). But too much consumption and not enough consumption can't both be problems at the same time.
> But too much consumption and not enough consumption can't both be problems at the same time.
What if the the problem is that the demand is for things that Japanese companies have a hard time producing? E.g., oil/energy (which of course actually is a big problem in Japan), iphones, etc...
If you then say that consumers aren't buying enough and there isn't enough demand, then that could also be a problem (recession). But too much consumption and not enough consumption can't both be problems at the same time.