It seems I'm not smart enough to find direct information on how to remove a default workspace created upon a new member joining in Prefect. There wasn't documentation or GitHub issue specifically addressing this exact scenario.
Default workspaces often serve as personal sandboxes for users, and the ability to delete or hide them might be limited by the platform to prevent accidental data loss or ensure everyone has a personal space for testing and development.
The best approach would be to check the administrative settings in the workspace interface within Prefect Cloud or reach out to Prefect's support team. They'll be able to provide up-to-date assistance on customization and workspace management. You can also explore if there are options to set permissions and visibility for different workspaces.
Since the databases of these workspaces are typically independent, keeping a "default" workspace may not interfere much with the main one you intend to use. But just in case you wish such a feature were as easy as hitting an "off" switch—it might not be quite that simple. C'est la vie in the world of structured data management!