sorry if this might be seen as threadjackin….
im am looking for almost the same thing but just the other way around:
i want to keep my access restrictions that work but want to disable any restrictions for attachments.
reason for this: i am using an addon called WP Media folder(https://www.joomunited.com/wordpress-demo/wp-media-folder/) that does not seem to work in combination with URE.
When i remove the restrictions from a certain user it works, but as soon as i restrict something the user does only see his uploads and only when using the media library entry in the menu section and he can olny access the media root when trying to add media to a page.

I was hoping that removing attachment restrictions from attachments but keeping it for the rest might be a good work around.