That does bring up a cool concept to add to the in game hub as a download option though.
If you could have a temp addonpackages folder that was session specific, you could test out a new resource with a copy of all the dependencies, with a "temp download" option that paths to the temp folder. If you won't be using it again, it just deletes everything you downloaded for the session when you close it. If you like the scene/look etc., you could click on the menu and save it to your main AssetPackages folder to keep it permanently. That would save on so much bloat in AddonPackages and speed up everyone's vam.
It's hard to get rid of vars you won't use again the way things are, because of the dependencies that come with it.