I feel the Elixir of Tongues is setting a precedent. If they are putting this in the game, it seems Blizzard is finally admitting the language barrier between factions, is not needed. And by extension, the faction split itself is not needed.
I for one am happy if this is indeed the direction they are going. I think the faction war is extremely stale. Going from all races being accepted into our Order Halls to a faction war where you are fighting against some of those same companions is ridiculous. Legion had basically zero faction specific content outside of a few quest hubs in Stormheim and felt like the story-telling was much more on-point.
Players should be able to go to the next step and group with players from the opposing faction to complete PvE content. Battlegrounds and arenas should allow you to make a team of both Horde and Alliance characters, and fight teams of the same. This divide of the player-base which invariably gets lopsided needs to end.
The Alliance and Horde should basically be a PvE/flavor/cosmetic choice... like the Aldor and Scryers were in BC. You could align with whichever one you chose. Could not enter the opposing side's base. Earned different looking but, equal armor and weapons. But both Aldor and Scryer players could always group together for dungeons, raids, and battlegrounds...
What do you think?