> adjusting tens of thousands of smart thermostats at once, effectively moving their electricity usage to a time when there is less demand
Somewhere amongst this was a great opportunity for reducing consumption of electricity from dirty sources, mass-optimizing millions of thermostats, car and electric bikes/etc charging, refrigerators, computer power settings etc to reduce emissions... but now it sounds like it should be illegal.
Actually there are some utilities out there with programs like this!
My local utility has basically this program.
Sweden have by hour and more recently by 10 minute electricity billing. Companies use it in automatic load balancing, car chargers use it, and IoT pilled dads in their 50s make home assistant schedules based on it.
It's pretty good! The need came from the high variability of wind power. Less dystopian than ... data centers... urgh.
It's of course optional. If you optimise well you can beat the monthly or daily tables and save quite a bit. If you don't care; you pay whatever the grid operator estimates.