It's perhaps accurate to say that it "ended" the French intellectual flirtation with Soviet communism, but that flirtation had been dying out for a long time by the time the book was published in 1973.

By 1956, when the Soviets invaded Hungary, and especially by 1968 when they invaded Prague, it was extremely difficult to sustain belief in the efficacy of the Soviet system of communism on the European left.

The Situationist International, for instance, was formed in 1957, partly as a reaction to this realization, which had been recognized by some socialist intellectuals like George Orwell as far back as the 1930's, that the Soviet Union was in effect a tyranny and was not on a path to liberation.

There had always been left opposition to the Soviet Union, from its beginning. This opposition was at times very strong, and came from mainly from anarchists and Trotskyists. Both had been treated badly by the Soviet authorities in the early days of the Soviet Union, the anarchists sailors of Kronstadt being crushed by the Bolsheviks and Trotsky himself and his followers being exiled from Russia. Thus there were a section of leftists who had become simply the enemies of the USSR.

After the Hungarian Revolution of 1956, and the Prague Spring of 1968, the lesson that the Soviet Union was behaving like an imperial power was fully absorbed into the European left, even among those who hadn't previously learned this lesson in the 1930's or before.

So it was that by 1968, when the May events happened in Paris, a New Left critique of Soviet communism had grown up, and those events were more influenced by other strands in left thought, either the Maoism that was fashionable at the time or the anarchism-influenced Situationism.

"Too many corpses strew the paths of individualism and collectivism. Under two apparently contradictory rationalities has raged an identical gangsterism, an identical oppression of the isolated man." wrote Raoul Vaneigem in 1967, in his book "Traité de savoir-vivre à l'usage des jeunes générations" (published in English as The Revolution of Everyday Life).

So on the radical left, there was already an anti-authoritarian tradition which could be called on to critique Soviet abuses of power.

Another fashionable trend associated with the French intellectual classes at the same period, of course, was post-structuralism and post-modernism. Post-modernism itself has been defined as "incredulity towards meta-narratives" (meta-narratives like international socialism) and tends to mitigate against political action in favour of theory and a field called "criticism". Someone like Julia Kristeva (described as a "flaming Maoist" by Noam Chomsky when he first met her) by the early seventies had transformed into a full-fledged post-structuralist.

So, to sum up, the statement is probably accurate but it has to be noted that there were other factors at work at that time which had also caused the French intellectual classes to be disillusioned with Soviet-style communism.