Question Where have my project files gone and how can I get them back?

Hello all,

Three days ago, I created a little project on macOS 11.6 using Unity Hub 3.0.0-beta.5 in editor version 2020.3.18f.1. I worked on it day and night, adding all sorts of assets I'd created directly in Finder to the project folder located at ~/Documents/Unity/Project.

This morning, I noticed that some of my sounds were not playing in the editor. This was strange, everything worked just fine last night. So, I decided to restart the editor to resolve the audio issue. When I returned to Unity Hub, it said that the project had not been modified in the last three days and then promptly updated to say that it had just been modified. When I reopened the project, all of the project files were missing. I now have a Scenes folder, containing the default 2D SampleScene, but that's it.

Does anyone know what might have happened? Could it be that Unity Hub created a new project with the same folder name, clobbering all of my files? I only just discovered Time Machine, so I am unable to restore the files that way.

Any suggestions for how to get this project back would be greatly appreciated . I should have used collaborate, but I also shouldn't need to be afraid that Unity's software will destroy my work.