News insiders across town were stunned to learn Monday that NBC exec Noah Oppenheim is being passed over for the top job at NBC News.

Division president Oppenheim had been “anointed” by Andy Lack as his successor.

But after Lack stepped down as its chairman on Monday as part of a massive corporate restructuring, Oppenheim now finds himself answering to a new boss. Lack’s position has been eliminated in the shake-up. But sources say that faith in both Lack and Oppenheim had diminished after a series of debacles at the network.

Last year, Ronan Farrow wrote in his book “Catch and Kill” that Oppenheim had decided not to run Farrow’s investigation into abuses by Harvey Weinstein, which later won the writer a Pulitzer after it was published in the New Yorker. Oppenheim has repeatedly denied silencing Farrow, saying that his work simply wasn’t ready to air.

And Page Six first reported that top NBC staff were furious when Farrow revealed that Brooke Nevils — who accused former “Today” show host Matt Lauer of rape — had told NBC’s HR department that Lauer had “assaulted” her. Oppenheim previously told staff that she had not alleged that Lauer had committed a crime. (Lauer has strenuously denied the allegations.)

“It’s a blow to Noah,” said an insider. “It was widely believed he had stayed at NBC because he was in line for that job.” Said another, “It’s the ultimate snub. They’ve spent the last year raising Noah’s profile.” Oppenheim will report to Cesar Conde, who will head the NBCUniversal News Group, which includes NBC, MSNBC, CNBC and Telemundo.

While he’s had a rough year, an NBC insider said Oppenheim’s leadership during the pandemic has been widely admired: “Noah’s shown his true colors.” Another NBC insider said the scandals didn’t help him, and added, “This is part of a broader restructuring under a new CEO across the entire company.”

NBC reps didn’t comment.