I pretty much agree. There seems a clear economic case to install enough grid storage to smooth out within day variations but that will fill up during multi-day windy periods so there will certainly still be periods of cheap electricity just not every day.

That likely means you'll still be able to charge your car cheaply most of the time but it probably makes home battery investments less attractive since you might only get 100-200 opportunities a year to charge it cheaply instead of 365, halving the annual savings.

But then given so much of the cost of a home system is in the inverter and control unit maybe it will become economic to buy several days consumption worth of batteries.