High absolute carbon emissions per capita? Which other countries? Here are the figures[0] for various EU countries using nuclear power, for comparison:
Country CO2 Emissions per capita (tons)
Czechia 10.53
Netherlands 9.62
Germany 9.44
Finland 9.31
So it's true that France managed low carbon emissions by committing fully to nuclear power long ago, but I don't think Germany is exceptional among EU nations for their failure to copy France's policies.> 2 - a low relative decrease in carbon emissions when compared to the improvements they could have achieved with the same amount of money.
How much money did they spend, and how much nuclear power could they have generated with that money? If the counterfactual you are comparing to is Germany somehow deciding to start build new nuclear power stations in 2011 (after the Fukushima disaster) then the amount of nuclear power they could have generated is zero, based on France's experience[1] with building Flamanville unit 3.
[0] https://www.worldometers.info/co2-emissions/co2-emissions-pe...
[1] https://en.wikipedia.org/wiki/Flamanville_Nuclear_Power_Plan...