I used the KNIME hub to share the solutions to problems we developed in class with the students of a data mining course (publicly shared). This was a year ago.
Now there will be a new course and the old solutions should be removed before we develop new ones.
I couldn’t find out how to delete/remove the WFs or the folder or set them to private.
If you login to the Hub from within the Explorer in KNIME AP, you should be able to drill down into your spaces and delete workflows from the Hub there, just as you would workflows in your local workspace.