There is no doubt that estate planning benefits people at all stages of their lives. However, it is also clear that the concerns of people in their 30s are often different from the priorities of people in their 70s.
What frequently happens is that a person (or a couple) makes an estate plan. And it sits. And sits. In fact, it sits for so long that it becomes outdated and inappropriate. If you have an estate plan, it could very well need a light or heavy update for these reasons.