Not impossible. A lot of the point of the island expeditions was to plant a ton of these smaller plot seeds everywhere for future storytelling. Dragon Isles and the void-infused ethereals coming back in the near future seem particularly likely.
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https://www.wowhead.com/quest=53170/...scale#comments
Seeded in BFA. Considering they already pulled out several of those seeds in later BFA patches I'd say it's a near guarantee. Just a matter of when.