Linking attachments / files that aren’t “supported” natively in Obsidian just got implemented a couple of versions back, and it’s extremely useful in my workflow. I think I’d just like them to be included in the Graph view aswell, so I can see the relationship to these files from pages.
I can imagine that an additional option in Obsidian’s settings to select if they should show up in the Graph or not… perhaps a third option where only linked un-supported files would show up as to not clutter up the Graph View.