Most peoples electricity usage is relatively inelastic and no one wants the cognitive overload of checking electricity prices before they put the TV on.
The same goes for an electric water heater.
The charger for your Tesla can also adjust when it charges based on power prices.
The dishwasher/washer/dryer can be set to come on at night when the power rates dip.
Exterior lights can dim if the power rates go up.
All that is needed is a way to get the spot price of electricity from the internet, similar to how I can get the current temperature in Anchorage. Devices don't need to talk to the power grid.
And if you're /not/ getting billed by the minute, what's in it for the buyer to choose an AC that sometimes turns itself off?
Of course, the power company having billing by the minute will then create the incentive for such an A/C. That's the whole point!
But you need everyone to be wired for this in order for a small change to add up to a big impact. Which isn't worth the cost unless it's mandated. Which is a political mess.
So we solve the problem another way; with batteries to meet the peak power demand at a reasonable cost, and not demand a massive IoT network, constantly monitoring usage and with override control authority.
The system will convert over as people normally replace their appliances, just like bluray has pushed out dvd players.
Most of benefits come if you have a system which can regulate slightly your use of air conditioning and heating (and a few other things like pool pumps).
In some cases you can save 50% of a daily powerbill by turning off the compressor in an air conditioner for 15 minutes.. but the right 15 minutes.
Few people would get up and turn off the air con for that, but a system that let you say how much you want to spend on it that you setup once makes a lot of sense.
What a great problem that will be.
You will end up with some kind of "smart device" router that connects to your internet/home network to talk to the power company, and uses a commodity wifi interface to talk to your smart devices. The cost of an ESP8266 is already sub-$7 at hobbyist volumes, you can expect the additional hardware cost to easily be driven to trivial levels with widespread adoption.
The problem is purely in getting a standard system out there and designing devices that incorporate the new control model.
Also, using a website or other resource run by the power company is still talking to the power company. Not sure ho else you could have parsed that, but you clearly had some crossed wires there.
It'll probably be more meaningful in some industrial plants though, if there's any such energy-intensive industry.
And if electric cars also plug in at work... jackpot.
Then all the rechargeable cars become part of the battery moderation of the whole grid!
That's a no-brainer compared to paying the owner for shortening the life of the battery.
Of course there should be some mechanism involved to prevent all washing machines to turn on at exactly the same moment the moment it dips...