This is what happens when an organization gets sufficiently large. And this is not necessarily a bad thing.
“Surplus” staff is very important when a new project comes and the organization needs to scale up. Instead of suddenly hiring a lot of people with no understanding of organization culture, the staff can be mobilized to work on new things without affecting existing project and structure.
There is a reason why governments around the world don’t suddenly fire their staff when it is apparent a lot of them are not working at max capacity. Redundancy is a kind of safety.