I’m not sure that would be desirable, since multiple things could potentially be referencing the same file. I agree, though, that it could somehow be made more clear that the onus is on the Bubble developer to manage uploaded files. There are a number of related posts. Just search the forums for “orphaned files”.
With regard to image handling, specifically, this post might be helpful. If your site is image-centric and you’re interested in optimizing your Bubble storage, a plugin like Upload Buddy might come in handy.
-Steve
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