That tendency is valid when you're plotting your own future strategy, because you can't go back in time. However when you're looking at society in aggregate, y

That tendency is valid when you're plotting your own future strategy, because you can't go back in time. However when you're looking at society in aggregate, you have to consider what will happen, so the conversation is still useful when planning for the future (since people will be at different points in their lives) of the group as a whole.