This would require adding a database index on image (img_user_text,img_media_type,img_timestamp) (or something along these lines) to make these queries efficient. (Otherwise they could take minutes or more for users who have uploaded hundreds of thousands of files, resulting in a DOS vector.) It can be done, but we'd need to steal some DBA time to okay the change, and the database migration would have to be planned in advance (I'm not sure how long it would take, but presumably on the order of multiple days).

I'm not sure if it's really worth it, to be honest… If you need such a list, I could easily write you a Quarry query (where it's not a problem if it has to run for a few minutes).

I mean, uploaders like to showcase their work, but having to maintain lists on pages manually is a hassle. This would also automagically solve that need for some of them, I guess (obviously not for the cases where they want to differentiate by topic, for example).
.