Is microfilm out of date? Why are libraries and archives still making microfilms?

In view of the defects of digital technology in the protection of ancient books and archives, the protection of ancient books and archives should also be based on microform technology. Even after all the original documents are digitized, these digitized products still need to be converted and processed from "digital" to "analog", and a series of products and corresponding software systems are integrated by digital and analog to realize the complementary advantages of microfilm and digital carrier.