>in that scenario you need nuclear capable of supplying ~100% of your power.

Where are you getting that from? Again, nuclear doesn't need to be a full backup, and nobody is suggesting we ditch renewables for nuclear. A perfectly viable solution would be a grid with a majority of power coming from renewables and storage, with enough nuclear generation to reduce the amount of overbuild necessary and to stop burning natural gas.

From this article:

https://www.sciencedirect.com/science/article/pii/S266627872...

>Individually, each firm technology delivers substantial cost reductions relative to portfolios restricted to wind, solar, and energy storage alone. Additionally, because each technology occupies a distinctive functional niche in the electricity system, having all of these technologies available optimizes the utilization rate of each resource and reduces system costs by up to 10% relative to cases with just one class of firm resource.