the cost of solar/wind depends on how much solar/wind is actually deployed.

1kWh of solar delivered midday, when there is 20% penetration? easy peasy.

1kWh of solar delivered at 2AM, when there is 65% penetration? much much more difficult.

These types of price comparisons are always unfair, always apples and oranges, because they always compare a 2AM kWh of nuclear with a midday kWh of solar, and of course solar wins that comparison.