[AdamJacobMuller]

Isn't that fundamentally a coordination problem?

When voltage is dropping (or phase is falling out of alignment) don't you want to shed load to stabilize? The issue seems to be more that too much load could shed too quickly causing wild oscillations in grid conditions from an undervolt to an overvolt. Seems like the correct, and not terribly complicated, solution to this is to have a process whereby the grid operator can request large customers to shed load and move to backup power temporarily.

That seems like such a reasonable suggestion that I would be shocked if such a thing does not already exist and is simply just not reactive enough and too manual.