Okay, TL:DR mode.
The Kaldorei have never been less numerous than they are now.
However, the Worgen Curse originated from their people, part of the machinations of Ralaar Fangfire, whom would come to be known as Alpha Prime and was instrumental in spreading the Worgen Curse across both the Kaldorei, and later on, the Gilnean people.
Most of Alpha Prime’s pack still sleeps beneath the Mother Tree’s roots in the Emerald Dream. Alpha Prime is dead, however, torn to pieces during the opening phases of the Gilnean content, and his Pack remains slumbering beneath the Mother Tree still.
Thousands of Kaldorei, many of them transformed against their will during the War of the Satyr as the Druids of the Pack turned on them in a frenzy of rage and bloodlust as Goldrinn’s ferocity overwhelmed their senses, and the followers of Alpha Prime knew this would happen.
We’ve seen that, with alchemical and spiritual aid, the Worgen curse can be made to be somewhat controllable, if never truly reversible. What if Malfurion decides enough is enough, and takes advantage of these coming three years of peace to reach into the Emerald Dream and, with the aid of the Gilnean Worgen and his remaining Druids, subject these slumbering Kaldorei Worgen to the same ritual and grant them their minds back.
Suddenly, the Kaldorei are no longer on the brink of extinction. The Worgen Curse isn’t transferred down to your children, so their species isn’t going to disappear in a few generations. A huge population of extraordinarily pissed off Worgen to occupy Ashenvale and bolster the battered and scarred Sentinels trying to keep the border secure.
It would make for an interesting Allied Race, drawing inspiration from two separate races, the Kaldorei and the Worgen, and their long slumber in the Emerald Dream may have altered their forms, both Worgen and Kaldorei, in ways not even the Arch Druid may have been able to predict.