If you have the same rainfall today as you do tomorrow, but tomorrow someone steals all of the water and leaves you with none, is that a drought? Not technically...but who the fuck cares about the technicality?? You don't have any water!
On a related note, many famous famines went from stressful-but-survivable bad harvests to mass casualty events because of mismanagement: the Irish Potato Famine, the Holodomor, the Great Leap Forward...
It seems the villain here could be the Chilean government, for prioritizing the tech economy over the people at a time when it matters most.
Yes, in your example, the person who stole the water would have stolen the water.
In real life, in Chile, who "stole all the water" ? How did they "steal" the water?