I this would impel me and others to glance at the graph view more.
I currently don’t look at the graph view as I see it most used for opening a reference note in the side bar and vise-versa.
I graph view in a separate window would also allow for more suggestions on how to improve the graph view (feature requests). If we don’t use the graph view enough it is harder to see where improvements can me made.
I have also heard of many opening notes within Obsidian.md simply to have access to the graph view.