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By design each Filenize action is a Queueable, this is slower than running the api’s directly in Apex. This is to prevent hitting DML/Callout limitations.
Executing a Queueable does not start the process directly, the process waits until Salesforce has the resources for execution.
Queueables are slower on sandboxes than on production orgs. This is Salesforce’s way to limit resources.
Since each action initiates an asynchronous process. The result of that process is not usable in the next consecutive process. For folder creation actions we do provide a direct output. As the new relative url is already known prior to the execution.