In my opinion Roon should never touch the music files themselves … deleting local content in Roon should just be a logical flag in the Roon DB to mark the music as “deleted”.
To maintain, I suggest that focus --> inspector should have an option to display “deleted” music, and then editing should be able to “un-delete” them if required.
If Roon / Roon users felt very strongly that Roon should be able to remove the files, then that could be implemented with a “Trash Can” purge feature … similar to Windows / Mac with appropriate warnings.