This feature is available in Catalyst, Enterprise, and Ultimate editions.
What is the "System (All Projects)" Project?
The "System (All Projects)" project sits at the top level of the project tree and was automatically created when Lifecycle was set up. We recommend that you create all of your projects/child projects underneath it to retain the flexibility to scale the project tree in the future.
If you have access to multiple child projects under the same parent project, but do not have access to the parent project itself, "System (All Projects)" displays instead so you can navigate to all of your projects.
For example, if you have access to "Project A" and "Project C", but not "Company", shown below:
The Project Tree shows:
System (All Projects)