Superluminal information transfer would be more useful for other areas than grid synchronization, but yeah we don't have crazy tech like that. And if we attempt

Superluminal information transfer would be more useful for other areas than grid synchronization, but yeah we don't have crazy tech like that. And if we attempt to synch to a 50hz frequency over the internet means a 10ms latency difference results in 180 degree out of phase input. And even if we did have the superluminal grid sync signal the propagation of electricity itself is slower than C and you'll need to consider perceived phase synchronization over distance.