The discussion of incorporating variability into the power grid is incredibly unsophisticated on HN.

The US (and Europe) are big places with diverse energy demand and weather patterns, and smart renewable energy developers will seek out resources that are decorrelated with existing supplies because the power can be sold at higher prices.

Batteries are also getting cheap enough to profitably arbitrage intraday price variability.

Another thing that gets ignored in these discussions is that in any net zero scenario there is going to be a fair bit of green hydrogen/biofuels/synfuel produced for transport and industrial use. A fraction of that could be diverted to gas peaker plants when monster dunkelflautes manifest themselves.