I do remember in Cataclysm, that the Horde made a Portal between Orgrimmar and the Dragonmaw Clan’s first outpost by using Elemental components and energies, so it may be possible for these ‘Portals’ to the Kaldorei’s former/current territories are running off of the ‘Divine’ magic of Elune instead, or powered by the energies of the Emerald Dream.
We did get that one line from the Forsaken-retake-Lordaeron questline with Cauliflower and CO. that all of the Primal Powers can be used to do the same things, its just easier to use them for specific things.
I don’t like that Bel’ameth is so far removed from Kalimdor, but I do appreciate it offers the Kaldorei so much safety. They’re right next door to their most venerable allies (even if they, along with the Wild Gods, did jack-all to save the Kaldorei in their darkest hour, but the Wild Gods might have been told to stay away by Elune …), they’re significantly removed from their rivals, they’re right next door to the Emerald Dream in a very literal sense so they can just funnel their people into the Dream if pressed and, post the Battle-for-Azeroth expansion, almost all the natural resources in Darkshore have been expended and the land is ravaged, not only by the war between the Forsaken and the Kaldorei, but also by Deathwing’s visit, the Twilight Hammer Cults and the Naga invasions.
Taking back Darkshore is a pyrrhic victory at best. Ashenvale certainly is a good home for their people but its still infested with Demons, Satyr, Fel-corrupted Furbolgs and now Old God corruption. The Kaldorei grip on the ‘rest’ of their territories, Stonetalon, Desolace and Feralas, was tenuous at best even before the Battle for Azeroth, with a handful of outposts that could barely support themselves and garrisoned by skeleton crews of Sentinels and whose supply lines went right through Horde territory or regions infested with relentlessly hostile centaurs, gnolls, harpies and worse.
The Kaldorei have been in decline for 10,000 years, and have been taking L’s the whole time because of their ‘Duty’ of protecting the Well of Eternity and their refusal to accept their ‘claim’ to Kalimdor ended when their society Sundered the planet. They were militantly against the Arcane, mistakenly believing that the Arcane alone was what drew the Legion to Azeroth and that if nobody used it ever again, the Demons would not be able to find Azeroth a second time … but then they joined hands with the Alliance, full of Mages and Warlocks, and then as they continued to take L’s for years after that until they allowed Mages back into their society just to try and hold back Garrosh’s version of the Horde.
This nearly led to a purge of Teldrassil as a result due to Maiev being entirely unhinged and having a massive number of Wardens and Kaldorei agreeing with her that all Mages, and all those who supported them, had to die to ‘purify’ the Kaldorei and make Elune smile on them again.
The Kaldorei need to have a safe place, removed from everyone else’s 
, to stop, heal, rebuild their society to be less hypocritical and held together through trauma and martyrdom and figure out what they are meant to do, and who they want to be, now that protecting the Well of Eternity is no longer their burden to bear. To accept that their ‘Empire’ ended 10,000 years ago and that now, they’re no more and no less than any other race on Azeroth and to let go (as much as anyone can) of the trauma of their past. There’s freedom in that, that they can no choose to be something more than grim sentinels in ancient forests, that the burden of atoning for what their people did 10,000 years ago no longer weighs them down, that they can try to be a people again.
Edit: I just realised something.
All of the Kaldorei’s former/current territories are in a bad place. Resources expended or filled with enemies.
Ameredrizzle and Bel’ameth are the only safe harbor on the Dragon Isles for Trade now. The small docks we have in The Waking Shores is infested with feral Proto-Drakes and Djaradin Giants. The Fishing Village of Iskaara is certainly accessible, but filled with Rot-worshipping Gnolls right above this region as well as multiple colonies of hostile Gorlocs, and the ocean is full of drifting ice-chunks and micro-glaciers that could sink a ship easily in bad weather.
The Kaldorei are about to become the sole ‘safe’ harbor into the Dragon Isles with Bel’ameth being not only a safe harbor but far more accessible to the Dragon Isles from Kalimdor or the Eastern Kingdoms from a position standpoint. That is a lot of tariffs and merchants coming into their lands, a lot of wealth, political influence and favors to be gathered and used in the future.
This may be, long term, the beginning of a new Kaldorei Empire without the xenophobia and imperialism of their old society, and tempered with Bel’ameth’s connection to both Life and Death and being a direct conduit for Azeroth’s will, given it empowered the six Draconic Aspects with versions of its own power, this could put the Kaldorei into a position of great influence over both the Alliance and Horde.