Sean Bailey, the longtime president of Walt Disney Studios Motion Picture Production, resigned Monday amid a leadership shuffling at Disney’s film division, which has been under attack by some investors for disappointing results at the box office.

“The time is right for a new chapter,” Mr. Bailey said in a statement.

Disney named David Greenbaum, a co-president of Disney’s art film division, Searchlight Pictures, as Mr. Bailey’s successor. Mr. Greenbaum, however, was given a bigger job, overseeing both Mr. Bailey’s slate of live-action remakes of animated classics and 20th Century Studios, a Disney film division that manages the “Avatar” and “Planet of the Apes” franchises.

Mr. Greenbaum joined Searchlight in 2010. He previously worked at Miramax when it was making films like “There Will Be Blood” and “No Country for Old Men.” He recently helped Disney win the streaming rights for “Taylor Swift: The Eras Tour.”

“David has an incredible sensibility and eye for film,” Alan Bergman, co-chairman of Disney Entertainment, said in a statement.

Matthew Greenfield, who was named co-president of Searchlight with Mr. Greenbaum in 2021, was given sole oversight of that division, which is known for Oscar-winning prestige films like “12 Years a Slave” and “Nomadland.” Searchlight’s current Oscar contender, “Poor Things,” has collected nearly $100 million worldwide; it cost $35 million, not including marketing.

Mr. Bailey was a production president at Disney for 14 years — an eternity in Hollywood, where film chiefs are often jettisoned every few years. Over that time, Disney was roiled by executive firings, restructuring efforts and shifting strategies for film distribution. The steady-handed Mr. Bailey, who is popular with stars and their agents, helped provide stability.

His hits included the live-action “Aladdin,” which collected $1.1 billion at the box office. A photorealistic “The Lion King” took in $1.7 billion. A live-action “Beauty and the Beast” delivered $1.3 billion.

More recently, Mr. Bailey’s division struggled — along with other Disney studios, including Marvel — to find new blockbusters. His remake of “The Little Mermaid,” which cost an estimated $375 million to make and market, collected about $570 million worldwide after its release last spring; Disney had hoped for closer to $1 billion. (Theaters and studios split ticket sales roughly 50-50.) “The Haunted Mansion,” overseen by Mr. Bailey, fell flat in July.

Mr. Bailey was a vocal supporter of diversity at Disney. A live-action “Snow White,” set for release next year, stars the Latina actress Rachel Zegler as the princess known as “the fairest of them all.” Halle Bailey, who is Black, played the title role in “The Little Mermaid.”

That worldview — and business strategy — increasingly put Disney and Mr. Bailey, a low-profile and self-effacing executive, in the middle of a very loud, very unpolite cultural fight. For every person who applauds Disney, there seems to be a counterpart who complains about being force-fed “wokeness.”

Mr. Bailey had shown signs of restlessness. In recent weeks, he talked to Netflix leaders about a senior movie position. Last year, he held similar conversations with Amazon. Three years ago, when he most recently renewed his contract with Disney, he made it clear that he it was likely his last.

“I know he’ll continue to do great things,” Mr. Bergman said of Mr. Bailey, who, at least in the near term, will become a producer on the Disney lot.

He will produce “Tron: Aries,” a follow-up to “Tron: Legacy,” a 2010 movie that he also produced — catching the eye of Disney leaders, who recruited him as an executive.