Most things in a modern home don't care about frequency. The problem is mostly at the generation end. The electrical grid is essentially distributed transmis

Most things in a modern home don't care about frequency. The problem is mostly at the generation end. The electrical grid is essentially distributed transmission locking all the generators across country together. They will all rotate in sync at the same speed/phase, it might as well be a mechanical linkage. The entire system is under too much load and the generators are all physically slowing down. Unfortunately the generators are all designed to operate over a very narrow frequency range. If the frequency continues to drop, the safety systems will kick in to protect the generator. If the load isn't reduced, more and more generators will drop off the network and there will be less and less supply to meet the demand. The frequency will drop lower and lower. Eventually the whole network will drop to zero and nobody will have power. It's basically the same thing as stalling an engine.