On the other hand, you have the survivors of the old French empiricist tradition.  No good examples really come to mind at the moment (Braudel, perhaps?

As it happens, in the very next sentence, Anderson says:

Historians were least prone to such an import substitution of literature, but even Braudel was not immune to the loosening of controls in a too flamboyant eloquence. It is this trait of the French culture of the time that has so often polarised foreign reactions to it, in a seesaw between adulation and suspicion.

Anderson is trying to identify some general features of French intellectual culture at the time which were dominant and very influential outside France (e.g. the people you cite).

Significantly, in considering exceptions to his generalisation you say:

No good examples really come to mind at the moment  

He would, of course, acknowledge that French culture even during this period did include many empiricist works. But they were not at the top of the hierarchy which existed:

Traditionally, literature had always occupied the summit on the slopes of prestige within French culture. Just below it lay philosophy, surrounded with its own nimbus, the two adjacent from the days of Rousseau and Voltaire to those of Proust and Bergson. On lower levels were scattered the sciences humaines, history the most prominent, geography or ethnology not far away, economics further down.

Also he is talking about those works which had national and international influence:

The reception of this effervescence abroad varied from country to country, but no major culture in the West, not to speak of Japan, was altogether exempt from it.