I see that you are angry but "completely useless" is not really helpful. Anyway I'll bite, I work at a startup that does demand side flexibility with electric

I see that you are angry but "completely useless" is not really helpful. Anyway I'll bite, I work at a startup that does demand side flexibility with electric hot water heaters (and working on other devices as well). We install our controller at customers homes and steer the water heating according to: electricity spot price, greenness of energy and also participate in frequency stabilisation markets. Customer saves by using cheaper electricity and earning money by allowing their heater to be used in the grid stabilization, in effect they get the money that would have gone to the gas peaker plant for firing up during an imbalance event. A 300L water heater stores about 16kWh of energy as heat and has a heating power of about 3kW. Aggregating thousands of homes together and making sure the water is heated when it's best for the system is one of the ways we're working on the problem of intermittency. The funny thing is that in our key market (Finland) the homeowners have dimensioned their water heaters to only heat at night when the electricity was usually cheaper. This meant that a family of 4 could use water all day without it getting cold and heat it during the day. Now we can flip this around and store energy when it's best. Demand side flexibility is key (along with storage and electrification of transport and heating) to enable green renewable generation to come up to the levels we need. Sure, we don't have solutions for the last 1% of the problem but we're far far away from the last 1%.