Apparently this is intentional.

if you update your transcode keys the api is not how you purge the database of expired keys

It's not of course. But it's kind of annoying when we have stale entries in the database because the cleanup script has not been run. Especially for users, who see an entry or that they cannot interact with when it has failed or when other entries have been updated, but these havent.

I don't really see the difference between deleting file and requeueing for 1 key, and only deleting for another (disabled) key. You already need to be autoconfirmed, and the action is logged, both can be abused in the same way in bulk.

Change #1226349 had a related patch set uploaded (by TheDJ; author: TheDJ):

[mediawiki/extensions/TimedMediaHandler@master] Api: enable transcode reset to reset a disabled transcode key

https://gerrit.wikimedia.org/r/1226349

Change #1226349 merged by jenkins-bot:

[mediawiki/extensions/TimedMediaHandler@master] Api: enable transcode reset to reset a disabled transcode key

https://gerrit.wikimedia.org/r/1226349