...Greetings, my Warcraft Loremasters.
I know this is a bit of a controversial question for some but I feel like at this point it's worth serious discussion and consideration.
As we all know, there are limitations that come with telling a fleshed-out story in a video game and let alone an MMO. The Warcraft Universe is no exception and more so since Cataclysm. There have been so many branching storylines it's a shame so much has been left behind.
On the one hand I do agree with those who say Blizzard needs to be careful not to religate too much storytelling to books or novelia. I don't think they've made that mistake yet personally on that note. With the Cataclysm to MOP transition they included the Theramore Bombing as a pre-expansion event to explain Jaina's Heel turn. The immediate aftermath is delved into more in Tides of War. My point is there was overlap and that's important. This was repeated with the Legion to BFA transition with Elegy/A Good War and their in-game equivelants.
Someone can feel free to correct me if I'm wrong on this but I believe The Shattering was the first novel that covered a lot of huge lore development that didn't get overlap in-game. Stuff from Magni being petrified and Moira returning to Ironforge to Thrall stepping down and naming Garrosh his successor, stuff like that. A LOT of stuff went down in the novel and I remember a lot of folks on MMO-C being pissed off because almost all of what was covered in that novel didn't get overlap in-game. I pity those who ignore or dismissed Lore expanded on and explained outside the game personally on that note.
I think all of us can agree there is only so much time you can give everything in the game itself. Some stories would be better explained via a different medium. It would also allow Blizz to actually go back and clean up a lot of loose ends from past expansions while still moving the current story forward at the same time. The can also explain some moments that happened in game from different perspectives and properly canonize certain cross-faction events such is most of BFA prettymuch (Blizzard confirmed Lorewise, the Alliance won both Warfronts for example).
Some stuff you can make a short story, other stuff you need a full novel to explain things in detail. Hell, the first WarCraft game was used as a base to make a movie. I just think the WarCraft Universe has gotten so big, it needs to be allowed to freely expand into other mediums is all. That's just me though. I attached a poll to this to get other thoughts on the matter.