But his rapid fall from Fox News (FOXA) amid allegations of repeated sexual harassment could leave the conservative star in a deep hole that's hard to dig out of.
As of Wednesday evening, the network had already removed O'Reilly's name from the show's title.
O'Reilly has denied allegations of harassment - including sexual harassment - despite payments from the network and himself to keep at least five accusers from going public, according to The New York Times. Both the self-proclaimed "no-spin" host and the network always claimed that the accusations were completely unfounded, but they agreed to pay a six-figure sum to one complainant in exchange for her silence and promise not to take the matter to court.
O'Reilly's attorney said on Tuesday that the host was the target of a "smear campaign" funded by far-left advocacy groups.
Rupert Murdoch's empire and in particular Fox News was enriched by the advertisers who fell over themselves to get into the ad breaks on O'Reilly's top-rating show.
Up to four million viewers watched "The O'Reilly Factor" each evening, making it the most-watched cable TV program in 2016 and generating $446 million in ad revenues for Fox between 2014 and a year ago, according to a study carried out by Kantar Media.
For Fox executives, it was not clear when it would end.
O'Reilly's exit, which was first reported by NY magazine, follows that of former Fox News Chairman Roger Ailes, who was forced to resign in July after being accused of sexual misconduct by a number of women, including former anchor Gretchen Carlson.
More than 50 companies yanked advertising from his show, the most popular in U.S. cable news watched on average by 3.98 million viewers in early 2017, according to Adweek.
Fox said Tucker Carlson would move into O'Reilly's time slot - the second time in three months he's replaced an exiting prime-time personality. It's the top-rated show on the No. 1 cable network - one that, according to the investment bank Nomura's estimates, accounts for fully 20 percent of profits at 21st Century Fox.
The show itself will be removed from the lineup beginning Monday. NPR's David Folkenflik reports that Walsh went through Fox News' formal complaint process, alleging O'Reilly made unwelcome advances during what she believed to be a business dinner.
Stephen Colbert, who mercilessly parodied O'Reilly on "The Colbert Report", paid tongue-in-cheek homage to the deposed host Wednesday on Colbert's late-night CBS show. He pushed a populist, conservative-leaning point of view born from growing up on Long Island, and was quick to shout down those who disagreed with him. "Half of the fun that they have with their audiences comes from watching the outrage that they manage to provoke".
"They could literally go dark during the time his programme airs and they would still be profitable", said Wieser.
Neal Shapiro, a former NBC News president, agreed that the loss of O'Reilly is hardly fatal.
O'Reilly's "Killing" historical series, including "Killing Lincoln" and "Killing Reagan", have consistently sold 1 million or more copies in hardcover, a rare achievement in publishing, and his platform on Fox enabled him to promote his work. He has also had best-sellers with everything from the memoir "A Bold Fresh Piece of Humanity" to his most recent work, "Old School", which includes passages urging the respectful treatment of women.
On Wednesday, he was seated in the VIP section, where a photographer from the Vatican newspaper L'Osservatore Romano snapped a photo of Francis reaching out to shake his hand.