What Could This Mean?

Here is an actual sentence from an article I did not finish reading:

"In this context of political defeat and disillusion with the possibilities of subjective action, structuralism, with its discovery of a Platonic world of mental phenomena conceived on the model of Saussurrean langue, immune from material determination, historical forces, or the effects of social activity, and equally insulated from the illusions of subjectivity, transmuted the political alienation of a generation into the appearance of an apolitical, scientific approach capable of penetrating levels of humane psychological and cultural reality inaccessible to either traditional Marxism or Sartrian phenomenology."

-- Terence Turner, Bodies and Anti-Bodies, in Csordas, T.J. (Ed.) Embodiment and Experience: The existential ground of culture and self. Cambridge: Cambridge University Press, 1994, pp. 32-33.