"People in Japan tend to live a long time; elderly Japanese are expensive to care for because they spend so many years in retirement and because they're accustomed to a high standard of living and medical care. For any economy to stay healthy, there need to be enough taxpayers to support all the retirees. But Japan's population is shrinking and aging simultaneously, which means that the number of old people is skyrocketing just as the base of taxpayers shrinks."

Why not just set the retirement age up to mitigate that problem?