What does the Excalibrain plug in actually do?

Just watched this video from the usually great Nicole VH on Excalibrain: How to use the ExcaliBrain Obsidian plugin - YouTube

But apart from the parent/child/friend distinction, it’s not clear to me what Excalibrain actually does. All the features she talks about (local graph, filtering files that are linked that don’t exist) are all found in regular graph view.

What do people use it for?