This section exists due to relationships which have been set between the initiative itself and the corresponding releases. The Features section show the relationships between specific features and the initiative.
By unlinking the relationships at the Release level, this would allow you to remove this information from the view.
At this time because of the current flexibility offered, along with current priorities, we are unlikely to provide additional customization to hide this section from the view, but hope that the mentioned workaround can help. We hope you can understand.
I disagree
This confuses my users in the notebook view.