Again, price is irrelevant if there's no electricity available at all when you need it.

The implication that the energy couldn't be available when you need it is utter codswallop.

At $0.01/kWh, PV electricity, if converted to resistive heat, would be below the cost of Henry Hub natural gas heat. And this heat would be very storable in artificial geothermal at maybe 600 C, where it would lose < 1% of stored energy per month.

Would this have low round trip efficiency if converted back to electricity? Sure. But if the PV electricity is that cheap, so what?

When levelized cost is low enough, there's plenty of room for engineering to work around intermittency and seasonality.