Pinning certain tag groups as category list create a more folder-like structure, making it easier to search through your Asset manager.
There are multiple ways to search through the Asset manager like filters, the search bar, and suggested tags. One other way to do it is to pin certain tag groups as a category list in Settings. These pinned tag groups will show up as a dropdown menu in your Asset manager.
This resembles more a folder-like structure that can be more recognizable when users are coming from a previous situation where Assets were stored in a folder structure.
The order of the categories can be changed in settings to determine how they show up in the Asset manager.