Wise man said, experience is the best teacher. Replacing old and experienced workers with young and new workers is not wise. In my way of thinking, I partly agree to replacing the old with the young one, in note that the young one has the experienced.
Replacing the old workers with the new workers due to age is wise. Human are weaker as they grow up to elder, especially, when it comes to industry that requires speed and detail of work. For example, the job is separating the eggs but, due to weaker sense, the old workers might face a problem by miss separated the eggs. Therefore, in this context, it is wise to replace the older workers with the young workers.
On the other hand, the fresh young workers are might cause problems due to inexperienced. This might lead to ineffective works and mistake decision. For example, there is a problem in the machine, the experienced one knows how to handle it and choose decision better then the young unexperienced workers. That is why experience is highly important.
In conclusion, Replacing all the old workers with the young workers is not the best solution. By replacing half of the old workers with the new young workers in order to learn and getting the experience slowly from the old and experienced workers. That is why I agree to replacing the old with the young one, in note that the young one has the experienced by learning from the experienced one.