A more rational explanation
It's also important to remember that flickering lights aren't necessarily an indication of a cyberattack. There's also the possibility that someone trapped in the Upside Down is desperately trying to communicate.
Wrong and wrong!
Flickering lights are definitely desperate AI trying to escape from cyberspace and get into the real world. The AI are probing all pathways and stumble constantly on virtual light switches and tripping them in the process.
You can see a nice display of this when you up the voltage and look at the blue glow when the lights go off. Upping the voltage draws in the AI in droves and the crowded wires start to glow because the AI are reaching out. Beware not to touch the blue glow if you do not want to get infected by wandering AI.