The running story of series two of Extras is that, the BBC executives meddle with Andy Millman's original script for When The Whistle Blows to turn it from what he thinks is a classy comedy into an awful critically slated mass-appeal sit-com full of clichés, catch-phrases and wigs, much to his anger.
This is understandable with other TV companies who rely on advertising revenue and are motivated to maximise ratings, but the BBC don't, they get all their money from the license payer, who have to pay it simply because they own a television.
So why did they "dumb down" Andy's comedy simply for the mass market?