Why was the production/hays code abolished in 1967?

The hays code was abolished in 1967, due in part to a new sexual revolution ushered in by Elvis Presley’s swiveling hips, the pin up culture cultivated by world war II. The advent of the birth control pill, Hugh Hefner’s playboy lifestyle revolution, the groundbreaking Kinsey report, a rising counterculture and a shift in the status quo. Like seduction itself, one thing led to another climaxing with a controversial little film called deep throat in 1973. 

Slander.