Foucault traces the repression-expression discourse surrounding sexuality from the middle ages, when people lived under the imperative to stay silent about sexuality most of the time, and the imperative to disclose sexual thoughts and experiences in confession, to the present time. Today, sexuality is everywhere; it sells beer and cars, it is marketed as pornography, it is taught about in schools (and some protest against this teaching), it is studied and researched by professionals and meditated on by many others interested in uncovering and understanding their true sexual feelings. Society is anxious about and on the lookout for sexual deviants. Left wing radicalism has often shifted its focus from a Marxian-economic perspective to an imperative for sexual liberation. Sex is the hot topic of the day (no pun intended). Even the voices who speak out against its necessary suppression have gotten louder, intensifying the entire repression-expression discourse. 
Foucault explains that our society has become highly sexualized. The problematization of sexuality is peculiarly pervasive in the West today.