Speaking on Monday at a press event on the eve of the Consumer Electronics Show in Las Vegas, Hirai thanked supporters who stood by the company in the face of the massive cyber assault, including employees and movie-goers who saw the film when it finally hit theatres.
"Freedom of speech, freedom of expression, freedom of association - those are important lifelines of Sony and our entertainment business," Hirai said.
His comments were his first public statements about the attack on the Japanese company's film and television unit.
"We are proud of partners who stood up against extortionist efforts by criminals who attacked Sony," Hirai said.
The Interview is now showing at 580 independent theatres in the US, in addition to online platforms, according to Hirai.
"I want to thank all the partners who made this possible, media who supported the launch, and those who have gone out to see the movie," Hirai said.
The November cyber attack against Sony led to an online leak of employee information, unreleased films and embarrassing in-house emails.
The hackers also mounted threats against Sony over the planned Christmas release of The Interview, which depicts a fictional CIA plot to assassinate North Korean leader Kim Jong-Un.
Threats by hackers issued after the cyberattack on Sony Pictures initially prompted the movie giant to cancel the film's Christmas Day release, after many large US theatre chains got cold feet.
The comedy, starring Seth Rogen and James Franco, eventually opened on December 25 in more than 300 independent movie houses that offered to show the film after Sony came under fire for pulling it.