> Obivously, the meaning of the original sentence is that miners will turn off the mining equipment when they decide that it's more profitable to leave it off than leave it on.

Well, it all depends on price of electricity in your region. If you mine for almost free using solar/other renewable energy/your energy is subsidized by government then you will still make profit while miners in high cost electricity regions will stop mining. If they stop mining difficulty will drop, which means you will get more money for mining.

This is self regulating mechanism, as long as bitcoin will have value it will be profitable to mine for someone.