
Is there any real reason for why the majority of leaks and theories are so convinced that we're going to Avaloren in 11.0?
a) There is a very short list of areas that are known but not explored.
b) There are multiple hints of new lands in DF in every patch. Avaloren and Khaz Algar at the prepatch. Then Nightsquall story supports Avaloren further. Then the tales of that green dragon who flew west.
The expansion has to take place somewhere. A revamp is unlikely, at least not for 11.0. What is left is a small number of unexplored islands and underground areas which are almost all disconnected (though Blizzard absolutely could pick a small area and make an entire expac out of it; they did it with Broken Isles but then they had an extremely strong theme (Burning Legion invasion) and equally strong system (Artifacts and Class Halls) to support it. More importantly, we don't really have anything pointing to them. There are usually plenty of clues in the previous expansions. Dragonflight has given plenty of clues but they all point to new lands and while not all of them point to a land beyond the storming sea (Avaloren), most of them do (Khaz Algar and Elun'ahir are not necessarily connected to Avaloren; the former very likely is elsewhere given that Watchers can observe there while they likely cannot observe Avaloren anymore).
I think it was to narrow down the number of mysterious undiscovered lands.
We know Avaloren exists and is hard to reach
We know there is a land far away covered by storm
We have a datamined Algarian Stormrider (Kinda the only actual hint for 11.0)
We know about Khaz'Algar
We know about the hole left by Elun'ahir.
Now, do we want these places to be all different?
Nozdormu didn't lay out any plan to prevent the infinites from corrupting him. Kalecgos and Alexstrasza completely gave up on laying out any plan to stop the primalists after failing to prevent their release. Ysera vanished like Malfurion trade off means nothing. The only ones that actually acted were the black dragons.
There is zero actions from the "good" guys that would make them feel potent or worthy of their title. It's useless bolvar all over again
Well I suppose once the tree is defended etc Ysera will head back to Ardenweald and Malfurion can return, but yeah, i agree that the Aspects/Dragonflights were rather useless this expansioni guess, the blues had to rebuild, so their storyline actually worked and we did some Bronze shenanigans, and the greens get their spotlight in the next patch, but seriously what have the red done?
I mean Bolvar was useless though. He lost the Helm which gave him his control of undeath and general psychic skills, he had his martial skills as a paladin but he did not have access to the Light anymore. And he still risked himself multiple times communing with the shards of the Helm and would join us in the front lines.

Spooky in dragonblight? Or this one?
Not to mention they lost their Aspect powers at the end of Cataclysm yet we were doing just fine for five expansions. So I'm not sure why it is so bloody important to get them back into their position.
Remind me again why do we have an entire expansion about the Dragonflights besides the vague notion that dragons are cool?
There are reasons to believe the hole of Elun'ahir is actually Un'goro. Il'gynoth in the Emerald Nightmare was inside the withered remains of an ancient world tree and the encounter takes place in Un'goro.
It sounds to me like there's something related to the roots of Elun'ahir below that area.