I can see you take it very personally and seriously. All what I offer is another perspective.

Malfurion and Tyrande are leaders of Night Elves as long as they exist like culture. They are amazing persons and they showed great ability to be flexible, but maybe it's time to make room for younger generation of Kaldorei. Maybe that is what they need in their situation.

Few days ago I read amazing idea that Nigth Elves actually can move to Gilneas with Worgens. Somebody said that Nigth Elves would never do that, because Kalimdor is part of their identity. However, that does not have to be thinking of young Kaldorei.

How we know, it won't actually happen. Tyrande will stay as leader and Malfurion will also very soon back probably. However, it's interesting to think about it.