Oscar winner Witherspoon, 39, shared a Time article discussing the diversity issue on her Facebook page Thursday, adding: "So disappointed that some of 2015's best films, filmmakers and performances were not recognized...Nothing can diminish the quality of their work, but these filmmakers deserve recognition. As an Academy member, I would love to see a more diverse voting membership."
Viola Davis doesn't believe the problem starts with the Academy at all.
The two-time Oscar nominee told Entertainment Weekly, "The problem is not with the Oscars, the problem is with the Hollywood movie-making system."
"How many black films are being produced every year? How are they being distributed? The films that are being made, are the big-time producers thinking outside of the box in terms of how to cast the role?" said Davis, 50. "Can you cast a black woman in that role? Can you cast a black man in that role?"
Although Davis said she won't be attending the awards show, she isn't boycotting. "I'm gonna be on vacation," she clarified.
Oscar winner Caine, 82, will also be absent from the Oscars for reasons not connected to the diversity problem.
He joked during an interview with Nick Robinson on BBC Radio 4 that he didn't want to attend to "sit there clapping for Leonardo DiCaprio. ... I'm too old to travel that far to sit in an audience and clap for someone else."
Still, Caine said he doesn't believe black actors should simply be nominated because of the color of their skin.
"You can't just say, 'I'm going to vote for him,'" he added. "'He's not very good, but he's black. I'll vote for him.' You have to give a good performance."
The nominations for the 88th Academy Awards, which will be broadcast on ABC on Feb. 28, lacked minorities in top categories such as Best Actor or Actress and Best Supporting Actor or Actress.
Actress Jada Pinkett Smith and her husband, Will, both said they would not attend the Oscars because of the diversity issue. Spike Lee has also been outspoken about the lack of diversity, but said Wednesday on ABC News' "Good Morning America" he instead planned to attend a basketball game in New York City.
Oscar nominee Mark Ruffalo contemplated skipping the awards show, but tweeted Thursday that he would "be going to the Oscars in support of the victims of clergy Sexual Abuse and good journalism. #Spotlight."
Ruffalo, 48, was nominated as Best Supporting Actor for his role in "Spotlight."
Academy President Cheryl Boone Isaacs released a statement Monday about the "lack of inclusion," saying that she is "heartbroken and frustrated."
Academy Awards CEO Dawn Hudson told The Hollywood Reporter on Wednesday that she was "devastated that the acting nominations were all white." She added that nearly 50 percent of their new hires in the last four years have been people of color, but acknowledged that the entertainment industry has "hardly moved" in the last 25 years.