France has 12% of Europe's population, and its primary energy is 45% from fossil fuels and 40% from nuclear power. The effect on Europe as a whole is therefore pretty small.
Also, France gets 70% of its energy from nuclear, not 40%.
No, it gets 70% of its electricity from nuclear.
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
Nope.
The most recent nuclear reactor (Civaux-2) was delivered in France in 1999.
The project aiming at building an EPR in France (Flamanville) started in 2004, and it was a work-in-progress on the field in 2007. Where are those "decades"?
Moreover an EPR was sold to Finland before, and work started in 2005.
Then a pair was sold to China.
Then another pair to the U.-K.
All 6 are very late and have huge overcosts.
If those 6 are in your opinion a "SINGLE reactor" let's swap my single dollar for your six bucks.
Not to count attempts to stem other projects (even in France, at Penly) by offering it to India, Slovenia, USA through UniStar Nuclear, Czech Republic, United Arab Emirates... The prospect weren't thrilled by patent problems at then ongoing projects.
There was a tangible will. As usual this isn't sufficient to succeed.
France also regularly sells its surplus to neighboring countries.
And in order to do that it has pretty massive lines to neighbours meaning it also acts as an exchange platform (for a profit) e.g. if there are strong winds it can buy electricity from an oversupplied german grid and sell it to italy.
https://app.electricitymaps.com/map/24h provides live views of the european electricity grids, and France is the only country which is consistently green (and often dark green aka under 50gCO2eq/kWh) without being blessed with enough hydro for most or all of its requirements (as Iceland and Norway are).