This really depended on the university. Some of them were not affected at all, some other had sections where you could not do any research or teaching without being from the "right obedience" (communist, Maoist, etc.)

The most extreme being (in French - https://www.deepl.com/fr/translator) the Vincennes university: https://fr.wikipedia.org/wiki/Centre_universitaire_de_Vincen...

[ TL;Dr: The most Maoist university at that time, with communists fighting (with violence) against Maoists inside the university ]

Note that this was a more "experimental" university, aimed to attract the most radical teachers (!)

There are plenty of research for the years between 65-75