Solas likes a bit exaggerate, when he speaks of destruction...
Trespasser ending:
S: "Thus I freed the elven people and, in so doing, destroyed their world."
I: "How did creating the Veil destroy the world?"
S: "You saw the remains of Vir Dirthara. The library was intrinsically tied to the Fade, and the Veil destroyed it. There were countless other marvels, all dependent on the presence of the Fade, all destroyed. The elven legends of immortality? All true. It was not the arrival of humans that caused them to begin aging. It was me. The Veil took everything from the elves, even themselves."
And:
S: "Had I not create the Veil, the Evanuris would have destroyed the entire world."
About Mythal:
S: "She was the best of them. She cared for her people. She protected them. She was the voice of reason. (...)"
About Cory:
S: "Corypheus shoud have died unlocking my orb. When he survived, my plans were thrown into chaos. When you survived, I saw the Inquisition as the best hope this world had of stopping him. (...) The plan was for Corypheus to unlock it, and for the resulting explosion to kill him. Then I would claim the orb."
What's next?
I: "That's the past. What about the future?"
S: " (...) I will save the elven people, even if it means this world must die. (...) I am not Corypheus. I take no joy in this. But the return of my people means the end of yours. (...) I would have entered the Fade, using the mark you now bear. Then I would have torn down the Veil. As this world burned in the raw chaos, I would have restored the world of my time... The world of the elves. (...) If they must die, I would rather they die in comfort."
So, summarize... When Solas says he intends to destroy the world - we have the accurate point of reference, as he once did - with the world of elves. And 4000 years later in Thedas elves, and even elvhen still exist... Removing the Veil and "world burned in the raw chaos" might simply means a new social order and other environmental factors. They do not expect the genocide, but rather the tsunami... I hope you know, what I means.
His description of Mythal, his friend, suggests what Solas valued the most. Calling him a racist, is a serious misunderstanding. I'll end on that, to not offend anyone unnecessarily.
According to the plane, Cory should have unlock an orb and ... die. These words strongly suggest that Solas wanted to remove the threat before it become one. Judging by the fact that the Magister lacked the power to remove the Anchor, during unlocking the same thing must happened, what happened in the temple of Mythal - death ... and rebirth. I can not in good conscience charge Fen'Harel for it, because Corypheus probably would have found another way to reach his goal. And during DA:I, in fact, attempted to... Without Solas and his knowledge about the Void, we'd be in deep sh...
What means "world of the elves"?
For the current Thedas? They will lose the slaves / cheap labor. They will therefore have to themselves take to work, impoverished... And they will not have no one to whom they could unload their frustration with impunity.
And the elves? They will once again be immortal, regain the old knowledge and the power of magic. They will soon dictate terms and be willing to settle bills.
And Solas may be referring to just that. Before you disagree, remember that at the time of Arlathan in Thedas also lived dwarves, so restoring the world of the elves, does not mean that other races must die... Well, unless people do not want to move to alienages.

Then it can go different ways.

Meh... seeing how Solas other "plans" went, I don't have much faith in his "Evanuris? Don't worry. I'll deal with them!" approach. After all the last time he tried that it didn't work out so well, did it? 
Therefore, Fen'Harel counting on the Inquisition or ex-Inquisition... 