Anything canon in WOW tends to revolve around groups of various sizes, there are multiple Maw Walkers just like there were multiple Hearts of Azeroth being pass out by Magni.
That was from the alpha version of https://wow.gamepedia.com/Torment_Chamber:_Thrall and was changed months before release.
I blame story writing on knee. All good people who worked on WoW storyline, left Blizzard long ago.
.
It's less of reclaiming the forge permanently and more reclaiming the forge for right now.
All the Covenant campaigns are also canon as they are mostly independent of each other and when they do converge each side has its own reasoning.
For example, in the Bastion Campaign, you want vengeance on the forces of Maldraxxus for attacking Bastion. This coincides with the Necrolords wanting that faction out due to them committing treason against Maldraxus. The goals are different yet similar enough that cooperation is possible.
A lot of the Campaigns have a similar overlap. I think the only campaign that's fully self-contained is the NF one.
Even if that usage of "you" is singular, it neither states nor really even implies there's only a single Maw Walker in existence. It could simply mean the faction leader NPC's trust the PC in question with Maw-related things because they're the one who saved them and also a Maw Walker. Other Maw Walkers may abound but didn't have a role in the specific PC's overall story.
"We're more of the love, blood, and rhetoric school. Well, we can do you blood and love without the rhetoric, and we can do you blood and rhetoric without the love, and we can do you all three concurrent or consecutive. But we can't give you love and rhetoric without the blood. Blood is compulsory. They're all blood, you see." ― Tom Stoppard, Rosencrantz and Guildenstern are Dead
I just want to point out my observations here and say this is false. I agree with the poster, that the game doesn't really show much of the other player characters and for the most part focuses on your character. But at the end of Theater of Pain, when they're congratulating you they refer to the party as "Maw Walkers" plural.
So the game does have a point of lore confirming there are multiple maw walkers.
What it doesn't have is that an npc or voiced character explicitly stating "You are not the only Maw walker." So yeah, you could play all of the shadowlands mistakenly thinking its a single player story because they never shoved in your face that there are other players. But an absence of proof does not equal a proof of absence. Until an NPC refers to you as the "Single, sole, ONE AND ONLY Maw Walker" then it's false. The game just never explicitly said "You ARENT", its only hinted or implied by dialogue like in ToP.
Venthyr overlap with Necrolords much more. And that part of their questline also happens after Denathrius is already dealt with in-story, making it a more likely candidate for a build-up for a future story.
And speaking of the Venthyr/Necrolord overlap (well, the first stage of it that was available so far), there are actually contradictions there that can't be explained with the usual, predictable and already existing in this thread "welp, the Kyrian forge was just retaken more than once because Blizzard kami-sama would never make a mistake". Because in the Venthyr version of the questline Kael'thas is purged of his sinstone before he goes on the Maldraxxi hunt. Moreover, Kael didn't go on Maldraxxi hunt knowing there were actual Maldraxxi forces in Revendreth.
He and the player just randomly stumbled upon the camp after stowing away on the Tithelord's carriage. And even getting on the Tithelord's carriage wasn't the plan as he didn't know we'd stumble upon him personally either. All he and the Venthyr knew at that point was that Tithelord had some deal with a Lich and that included someone smuggling weapons from Maldraxxus into Revendreth, at which point Kael decided to investigate things further.
Speaking of which, the Accuser left shortly afterwards the purging of Kael'thas, leaving him in the player's care. At which point Kael convinced us to investigate the matter further to provide the Venthyr with a "selfless act" to prove how oh, so redeemed he is. So, the player and Kael went to the town where Tithelord meets with his contact from Maldraxxus, as that was the only clue they had. And, like I already said, they just so stumbled on one such meeting, then stowed away on Tithelord's carriage, stumbled upon the Maldraxxi camp and dealt with it. After which you return to Sinfall and inform the Venthyr of the whole thing.
Yet in the Necrolord version when Draka goes with the player to deal with the same camp in Revendreth Accuser is there to greet her, being fully aware of the camp already. And when she introduces her to Kael and offers his aid in this mission, Kael is still carrying his sinstone, meaning he hasn't gone through the cleansing ritual yet. Then you go kill the exact same named Dredgers and the same named Lich as you do in the Venthyr version. Obviously there is no Draka in sight in the Venthyr version either.
I'm sure someone has already said this, if not then I will: Yes, technically only one is canon. The player character is a unique character within the world. There's not millions of over powered "champions". Lore-wise, the other players you interact with are just soldiers within the Horde and Alliance, with yours being the stand out strongest among them. So the covenant you chose is the one whose story is canon.
Not only has Blizzard stated this, but its also shown during Legion, when you go to deactivate Sargeras's sword, and you are there with lore figures representing the other class halls, all wielding artifact weapons.
If what doesn't kill you, makes you stronger. Then I should be a god by now.
That someone is you. Majestic plural is about using the plural pronouns when referring to oneself, not about using plural nouns when referring to someone else. Mawsworn referring to the players around them in what is a group activity as Maw Walkers has nothing to do with the royal we. Making your following reply to @Engal here:
quite ironic.
And a character that hasn't done Legion somehow still appears as an NPC defending the temple of Elune in Ysera's recurring nightmare about her attack on it. Blizzard being sloppy is nothing new, neither does it prove or disprove anything.
Given how each and every Class has an NPC stand-in for Sargeras' sword quest, if anything it indicates no player is actually canon and we're just stand-ins for characters that Blizzard usually just doesn't bother specifying.