This is only a proof of concept:
The plugin adds an admin-only admin/uploads route to browse and filter site-wide user uploads.
Features:
- List all uploads with thumbnails
- Infinite scrolling
- Filter by username and dates
It’s 99% AI-generated and the code wasn’t really reviewed. Don’t install it if you can’t review the code yourself and decide it’s safe to use.
I don’t encourage AI plugin development by non-developers, and this plugin should be considered as nothing but a proof of concept.
Now, if a developer wants to look at what is probably awful code, or use it as some sort of inspiration for a more serious and robust project, please do. 
Repo: https://github.com/Canapin/discourse-uploads-library
Edit: there is now a proper plugin that uses some relevant features (
Topic Gallery).
If the purpose is completely different from the #feature topic, the plugin also shows users’ uploads with filters and restrictions, in a browsable interface.