In launch/tags, you can’t delete a published lib. because it’s immutable for audit/versioning. Only unbuilt/unsubmitted libs can be removed. To overwrite, publish a new lib. to replace it. once a lib is published (any env incl prod), Launch/tags locks it, so you can’t delete it only replace it with a new publish.
Also refer to this to republish an old library:--
https://experienceleague.adobe.com/en/docs/experience-platform/tags/publish/republish
The five most recent libraries that have been published to your production environment on a Web property are available for later retrieval. This feature is helpful when you find a bug in your production library and need to rollback to a known good state immediately.
From your screenshot, if this is the first publish and you are testing it and want to remove it, the only way is to restart- copy all rules, data elements and extensions into a new property in launch/tags and use the new embed code in your dev/prod.
