The BBC strengthened its compliance procedures in 2008 after a series of controversies, including the 'Manuelgate' scandal over lewd messages left by Jonathan Ross and Russell Brand on the answering machine of actor Andrew Sachs during Brand's Radio 2 show.
Speaking at the Hay Literary Festival in Wales, Evans said that the stricter compliance procedures have improved the quality of comedy on TV and radio, but have also made some new ideas not worth pursuing.
"What has happened since [the Ross-Brand scandal] is very, very good but also a complete pain in the backside," he said.
"It means comedy has become much more sophisticated but the compliance culture that has come in since, you wouldn't believe it.
"The compliance department of the BBC is so extensive it's an unbelievable nightmare. Sometimes you come up with an idea and the compliance you have to go through is so great that you just say, 'Let's not bother'."
Talking to the Weakest Link host Anne Robinson, Evans said that the new compliance procedures have "completely changed broadcasting". The 45-year-old added that the Ross-Brand scandal was an "earthquake" that was "waiting to happen somewhere".
"It has completely changed broadcasting but broadcasting had to change anyway because post 9pm, on every panel show on television and lots of radio stations, the language was all going one way," said Evans.
"When you start low there's nowhere to go. It's like watching pornography - it's got to get more severe to get the same high.
"The laws of physics say that's a downward spiral. This earthquake was waiting to happen somewhere, it just so happened on that particular show."
Brand resigned in the wake of the 'Manuelgate' scandal, described by former BBC chairman Sir Michael Lyons as a "uniquely toxic combination of profanity, misogyny, bullying and black farce". Ross was suspended for 12 weeks without pay in 2008, and later left the corporation.
Evans said that Sir Terry Wogan had wanted to finish on the Radio 2 breakfast show shortly after the scandal, but agreed to remain for another year after the BBC put all moves "on hold". Evans took over the programme in January 2010.
Stephen Fry and Chris Moyles are among the people to have hit out at the restrictive BBC compliance procedures brought in after the 'Manuelgate' controversy.
In an interview with the Radio Times last September, Fry said that a culture of fear at the BBC was making the corporation's programmes "incredibly bland".