When a Salesforce org user creates a folder (for example report, dashboard, email template) they will have Manage Access to it. Once the user gets deactivated, the user will automatically lose Manage access to this folder.
This happens when the user is deactivated all the enhanced folder sharing records will be deleted, which will result in the removal of user access.
We can confirm user access through either the UI or the Rest API by following these steps:
Enhanced Folder Sharing in Reports and Dashboards: Considerations and Requirements
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