Nuclear provides guaranteed minimum power production, which is what you actually want. You also want a more diversified system than just eg solar and wind.
It's not acceptable to depend on renewables like solar and wind to try to fill that minimum guaranteed role. They are low on the guaranteed scale, whereas nuclear is high on the guaranteed scale. Grid scale batteries do not fill that role either, not under any scenario short of magic batteries that self-fill perpetually.
Paying the added cost for nuclear at 20-30% of total national energy production, is a reasonable price to pay for higher diversification and higher guaranteed minimum energy production.
We should also boost the grid and build nuclear in low-risk weather locations and distribute from there to everywhere else. Climate change is going to hammer the coasts, right? Perhaps a super hurricane knocks out solar and wind across multiple states around Florida. We bring the lines back up and immediately have nuclear power flowing in from weather-safe foreign states to re-start everything with (those out of state nuclear plants are already handling 20-30% of Florida's power in this concept; if rebalanced properly, they could handle 50-60%+ of all the now-lower power demands in the early re-start phase after such an emergency).
You can get high-concentration of power output capability in a weather-safe area with nuclear, in this model, which solar and wind can't even remotely come close to competing with.
