Maybe you are confusing with 2022 when half of french fleet was shut down to check for potential pipe cracks/corrosion esp in one of their reactor designs due to poor geometry. But that's unrelated to droughts
And of course, there is the what to do with the waste dilemma. And at least with current French park, there is a dependence on the rarer kind of uranium.
A lot of NPPs in France are cooled with river water and they need to be kept at low output if the rivers are too warm.