Delete multiple objects from workspace at once

Hi gmarc 
Thanks for using Fabric Community.
Currently we can delete only one item at a time in Fabric Workspaces. But folders in workspaces is an additional feature which is on roadmap. This would allow you to group all the old notebooks into one folder and you can delete the folder at once.

For more information please refer to this link:
What's new and planned in Microsoft Fabric UI and shared experiences - Microsoft Fabric | Microsoft Learn

You can also submit a feature request to Microsoft Fabric team for bulk delete functionality in the UI. 

I request you please share the feedback on our feedback channel . Which would be open for the user community to upvote & comment on. This allows our product teams to effectively prioritize your request against our existing feature backlog and gives insight into the potential impact of implementing the suggested feature.

Hope this helps. Please let me know if you have any further queries.