You thought correctly about the WBHV TV, Animation, and Sports folks handling Tom and Jerry. You thought incorrectly when you supposed they did not also handle the Looney Tunes releases.
I don't know if this has been talked about before, but it always annoys me and would seem pretty easy to fix. In the short "Buccaneer Bunny" there is a scene where Bugs is standing in front of a door that says NGER, UN, WDER. It is supposed to say DANGER GUN POWDER. If this scene had been windowboxed a little you could understand why Bugs was throwing matches in there to upset someone. I am not saying they should windowbox everything, but when important stuff is missing it just seems to be common sense to do this. I have seen many MGM Tex Avery cartoons where gags are missing completetly because of this.
Okay, I'm confused then. I know I've read somewhere that the Looney Tunes are handled by the same department that handles Casablanca, The Adventures of Robin Hood, etc., i.e. the classic films catalog department. Hence the 4K Ultra Resolution restorations. Did this change, and if so, when?
Who knows, then? It may just have more to do with a lack of interest on their part on the MGM cartoons. The Scooby Doo season sets are by the same people, yet they have A+ remasters. Tom & Jerry and Droopy have been handled with the least amount of effort. Perhaps it's because the existing MGM cartoon video masters are "fine" while the old WB cartoon transfers are generally 4-F in quality (except for the surprisingly nice quality transfers of the Harmon-Ising cartoons).
The Family Division folks answered some Looney Tunes questions because they were asked them and I guess did have some knowledge about them, but no, they do not produce the sets. Looney Tunes is indeed handled by the Warner "A" team.
Also, the theatrical catalog folks do not answer questions about the Looney Tunes when they participate in their chats. While Warner has separate marketing division for Theatrical New Releases, Theatrical Catalog, and TV/Animation/Sports (sometimes called TV and Franchise), I do not believe their organizational chimney is such that they cannot share technical resources. Not every animation release is treated like the Looney Tunes sets, but then again, not every theatrical catalog release is treated like "The Wizard of Oz".