Mainstream movies that show female genitalia (not just pubic hair) are exceedingly rare. People are still debating just how much of Sharon Stone was visible in Basic Instinct.
On the other hand, scores of mainstream movies over the past 35 years have shown male frontal nudity. Just a few:
Borje Ahlstedt, I Am Curious (Yellow) (1967)
Malcolm McDowell, If . . . (1967), A Clockwork Orange (1971), Caligula (1979), Britannia Hospital (1982)
Alan Bates and Oliver Reed, Women in Love (1969)
Michael Margotta, Drive, He Said (1971)
Don Johnson and Gregory Harrison, The Harrad Experiment (1973)
Alain Delon, Shock Treatment (1973)
Gerard Depardieu, Going Places (1974), Vincent, Francois, Paul and Others (1974), The Last Woman (1976)
Peter Firth, Equus (1977)
Graham Chapman, Monty Python’s Life of Brian (1979)
Michael Jeter, Hair (1979)
Richard Gere, American Gigolo (1980),
Cyril O’Reilly, Porky’s (1982)
Christopher Atkins, The Blue Lagoon (1980)
Kevin Bacon, Wild Things (1998)
Tim Robbins, The Player (1992)
Harvey Keitel, Bad Leiutenant (1992)
Ewan McGregor, Trainspotting (1996), The Pillow Book (1997), Velvet Goldmine (1998)
Julian Sands, Simon Callow, and Rupert Graves, A Room With a View (1985)
Antonio Banderas, Baton Rouge (1988)
Eric Stoltz, Haunted Summer (1988), Naked in New York (1993)
Sam Rockwell, Law Dogs (1997)
Jonathan Rhys-Meyers, The Governess (1998), Tangled (2001)
Jason Priestly, Calendar Girl (1993)
Mark Rylance and dozens of extras in Prospero’s Books (1991)
David Duchovny, New Year’s Day (1989)
Sean Patrick Flannery, Powder (1995)
Liam Neeson, Nell (1994)
Bill Paxton, Boxing Helena (1993)
Cillian Murphy, 28 Days Later (2002)
Edward Norton and several extras, American History X (1998)