Can fiberglass from inside of sand filter return to pool?

I have a 20 year old, 2 part Hayward fiberglass filter.
I decided to open it up today to change the sand...expecting to find broken laterals and what not.

To my surprise, it looks like the laterals and plumbing was replaced at some point becasue they look like they're in great shape - almost new.

However, as I was washing out the top half of the filter with a hose, I noticed that grass and some fibers were stuck on the surface on the inside of the shell. Looking closer and 'rolling' with my finger on the surface, I was able to scrape/roll off the fiberglass. It rolled off like wet dog hair.

My concern and question is: Does this sound like it's time to replace the filter, i.e. the fiberglass has deteriorated? Can lose fiberglass be returned to the pool or would it get filtered by the sand?

Thanks