I can't seem to understand what this question is asking, but I have tried to answer it. Can someone check it please? :)

Why were the epics of importance to the Greeks of the Dorian period?
Answer:

The Dorians were far less advanced than the Mycenaeans. The economy
collapsed and trade eventually came to a standstill soon after their arrival. Most
important to historians, Greeks appear to have temporarily lost the art of writing
during the Dorian Age.

3 answers

The question doesn't make sense to me.

Why were the epics of importance to the Greeks of the Dorian period?
Yes. I know. It doesn't make sense to me either. Dx Thanks for trying though. :)
IF they had lost the art of writing, the epics would have been highly valued, both as artifacts from a "better time" and as an example of how to write.