There is a Collapse All Tracks, but no Expand All Tracks. That is a problem indeed. Also, Collapse All Tracks is misnamed, as you can't collapse a track, only folders.
Importantly, the new commands for Hide Unused Tracks and Show Unused Tracks, while great and were long needed, miss items in collapsed tracks. I don't see this as a feature. I was hoping for Expand All Tracks so I could write a macro to get around the above limitation. The macro would, Expand All Tracks (folders really), then unhide or hide tracks.