Yes. For like the billionth time:
So was Draenor. So was Zandalar. So were the Broken Isles. But we still had BC, BfA and Legion.
This is a non-argument. We know,
objectively, that K'aresh wasn't atomized or fully destroyed in any capacity--Ethereals are still on it in some capacity they can actively go to and from it. It exists. It was destroyed in nearly the exact same way that Draenor was originally destroyed: ripped apart by the raw magical output of a vast number of portals to other planes. The Ethereals
fought back against Dimensius AFTER using their new more powerful forms to fight against the void for
years until he called in even more void forces to force them back. What were they fighting on if not the remains of the planet? Where were they forced to flee into the twisting nether from if not the remains of the planet?
This is Hawaii:
It is a (series of) insignificant pebble(s) on the surface of our planet.
This is that same Hawaii, specifically the 4th largest island in the chain, Kauai:
Even a small sliver of a planet is all you need for an entire expansion landmass, and in all likelihood, K'aresh
is probably hundreds of thousands of massive chunks of the planet. It is perfectly valid as an expansion location. Any pieces of it are almost certainly larger locales than the small islands of Kul Tiras, Zandalar, and the Broken Isles.