They should remove them at this point. It was a weird selling feature of an expansion, a way to gate looks and get players to do grinds while having it be a separate thing. It made sense from a give-me-money standpoint at the moment but it doesn’t make sense for the long-term health and elegance of the game and its design.
Allied races as a concept should be removed entirely. Instead allow players to choose from a racial/species variant at the character creation screen and in the barber shop, lock them to certain customizations based off their choice, change their racial name tag and references in game and just continue it as a means of player customization.
Vulpera are about the only truly unique, independent race and if Blizzard wanted to add them they should have gotten the dignity and still deserve the dignity of being a full race with a home city as Blizzard isn’t about to remove them. (For the record I do think their allied race questline is one of the silliest things ever made, it doesn’t show their capabilities, it shows your capabilities as the player at following orders and you’ve done that for everything up to literal objects that hand out quests as well as species that are frankly unintelligent and negligibly sapient)
Nightborne/Shal’dorei are in kind of an iffy area but I still say they’re just a variant of Night Elves/Kal’dorei. That said if Blizzard wanted to expand upon a variant of Suramar for them so they have a home city in one of the top 5 best cities that would be fine.
But I doubt Blizzard will do this, they’re going to continue trotting out locked variants of races and probably hold out hope they can re-use the allied race concept in a future expac as a selling point.
It’s frustrating too because if they dropped the whole concept and instead integrated them fully and fully embraced them as variants/customizations and allowed people to change them via the barber shop it would open up various long-wanted player choices with minimal art dept work. Things like forest trolls, actual high elves, ice/frost dwarf variants, etc.