How long do you expect to live? Until the age of 80? 100? If you had asked your parents the same question, they would surely have felt that a life expectancy of 70 was around average. Your grandparents, meanwhile, might have felt fortunate to live for 60 years. It is clear that people are living longer than ever before, but is this a positive or negative development?
On the one hand, increased life expectancy brings many opportunities later in life to try things that you could not do in your youth. Going on a world cruise, taking up a new hobby, even going back to university to get a degree: all of these opportunities are available to retired people nowadays. What is more, while many parents find raising children to be a stressful experience, spending time with grandchildren brings far more pleasure. Therefore, a more elderly population generally means a happier population with more time to enjoy life.
On the other hand, since elderly people often rely on the government or their children to support them, there are real concerns about the financial consequences of an aging society. Countries such as Japan are already being forced to raise both taxes and the age of retirement in order to offset the problem. Without a doubt, many other countries will need to take similar actions in the coming decades.
Overall, I would say that the benefits to individuals of living longer far outweigh the cost to society of supporting an elderly population. Of course, various countries need to take steps to ensure that the process is carefully managed.