If you suck on a tit the movie gets an R rating. If you hack the tit off with an axe it will be PG.

The remark is a blunt critique of American film-content standards: sexual content (even nonviolent, consensual acts) is often penalized more harshly than graphic violence. By contrasting an erotic act with a gruesome act of mutilation, Nicholson highlights what he sees as a cultural and institutional hypocrisy—one that treats sexuality as more morally dangerous than violence. The quote also functions as a show-business insider’s complaint about how ratings shape what filmmakers can depict, influencing scripts, marketing, and distribution. Its shock value is part of the point: the extremity of the example forces attention to the perceived imbalance in censorship and public sensibilities.