It is true that Nuclear Power Plants are base load plants but it is not true that it takes days to lower out put. It can be lowered in a matter of minutes.
That being said Nuclear Power Plants are not good Load Following plants.
Varying power drastically over the course of a day makes it more difficult to control power.
I won’t argue very hard with you...since you’re almost certainly right.
But answer this - does pulling back the rods actually “save energy” or do the reactants continue to decay anyway?