That wasn‘t what was mentioned, it was specifically mentioned they should use more nuclear to heat, I.e. use exceeds heat for district heating for example.

This is fairly common for coal and gas power plants, but as far as I know, not really used with nuclear power plants.

As far as I know, the French nuclear power plants aren’t exactly in close proximity to any major city, making district heating most likely not economically viable

It implies an adequate design, adapting (retrofit) an existing nuclear plant to such co-generation is very difficult.