I would love to see the old mega-fauna of North America, or return a recently lost species. But I wholeheartedly agree with the article that until their habitat is restored and the wilderness of the world respected, why bring them back with no home to go to? It seems like having a whale spontaneously materialize miles above a planets surface, highly improbable and short lived.
If people could learn to live around a more wild world, we could return large tracts of the continents back into relatively unbroken wilderness. The wilderness corridor movements come to mind, like this one to restore a
West coast corridor.
Once we have a place for them to live freely, I can see the value of bringing back animals. Like the Mastodon to go clean up the understory of western forests and in doing so help reduce forest fires back to their "natural" levels. Or passenger pigeon cloning then breeding in the billions, let those birds birds get back to their job of fertilizing on a continental scale.