The BBC is forbidden by its own charter from making everything in-house. I suspect there may be similar PSB licence conditions imposed on ITV. This was a decision initially taken in the 1980s as a means of privatising TV production without directly breaking up the BBC. It isn’t a situation that’s ever going to change. Even if it was thought desirable to do it, the BBC doesn’t have the capacity to produce everything in house any more. Last time they did so, they had only 2 TV channels and they both closed down overnight.
