Except fossil fuel production went UP when "renewable replaced nuclear".
While renewable was built out quite a bit and nuclear was decreased at roughly the same time, total demand has risen (as it tends to do) and that delta was filled by more fossil fuel production.
IMO (and many other peoples) the climate-positive approach would have been to keep nuclear, while building out renewables and phasing out fossil. And then try to build more renewables to get rid of nuclear, if that's still desired.