Following the link to the actual report (from the Wikipedia page) and searching for France brings data like:
[..] as France slipped down a category. France’s slip was the result of a deterioration in social cohesion.
and
The rise of the FN in France is just one example of an increased appetite among voters in western Europe for populist, anti-immigrant and Eurosceptic parties
and
The emergence of technocratic, centrist parties, divorced from the electorate, has created a political chasm between the outlooks of elites and the public. Into the gap have stepped the populists, who appeal to alienated electorates—what Marine Le Pen has characterised as “the France of the Forgotten”
And the numbers of each category of questions:
- Electoral process and pluralism 9.58
- Functioning of government 7.14
- Political participation 7.78
- Political culture 6.25
- Civil liberties 8.82
The worst number is for "political culture" which, for what I have read, related to the "faith" that people have in democracy.
For example, in page 52 you can look at the questions of this part, with questions like Perception of democracy and public order; proportion of the population that believes that democracies are not good at maintaining public order (if few people agrees then the country scores 1 point, if many agrees it scores none).
Of course, all of these reports are prone to "observator bias" (what is important to define "political culture" and what not? How important is political culture in relationship to a functioning democratic government, or public participation?) and other issues; usually it is way more useful interesting the trend a certain country is following in the last years/decades than the bare number/classification.