This assumes learning rates never seen by nuclear energy. Within generations we've seen small learnings, and between generations the nuclear energy has been all negative learning by doing.
Also not said is the fact that going into more standardized designs you lower the operational cost because operations can be standardized. Today every single facility has different training from the next. Even at the same facility, if it's got new + old reactors, operators can't move between them without training on both
This line of thinking seems to start with that we must have new nuclear, for some reason, and then try to rationalize it.
https://www.researchgate.net/publication/321765366_How_expen...
In term of decarbonization of electricity production and independence of imported fuel for electricity production, it got less then France for comparable amount of money.
But this is quite clear as the first and foremost goal of German Energiewende was denuclearization of German electricity production, not decarbonization of electricity production.