Michael Crick, who joined the BBC in 1990, said the station spent too much time “dealing with questions of race and gender and trans rights”.
In an interview with Roger Bolton’s Beeb Watch podcast he said: “If you just listened to Radio 4, then you would think that ethnic minorities made up half the population. That is the area I would look at if I were Tim Davie [the BBC director-general].”
He added that while the BBC’s news programmes didn’t suffer from the same “liberal, left-leaning” approach, instead “they have a problem with dullness at times and being too pedestrian”.
These views were echoed by an insider at the station who reportedly believed the issue extended to its news.
They told The Times: “There are too many people who have gone to the same universities and think the same things.
“Listeners are becoming alienated by endless lectures about racism, sexism, ableism and heteronormativity.”
However, while Mr Crick launched his withering attack, he acknowledged that Radio 4 faced a challenge in offering a range of views due to the political makeup of the industry.
He said: “You don’t get many right-wing comedians on the BBC, although GB News has managed to find some. And there aren’t that many right-wing people in the arts.
“So you end up interviewing people about what they think about [Donald] Trump, or the Government, and it all becomes highly predictable.”
Radio 4’s audience plummeted in the last three months to 9.3 million listeners from 9.8 million last year, Rajar data revealed.
Mr Crick also went on to add that Newsnight, where he worked for 19 years, is also past its prime.
He said: “Part of me thinks that they should just kill it off. There was a time when it was one of the glittering jewels of the BBC, but the days of spending weeks putting great interviews together and doing proper reporting? Hardly any of that happens.”