I agree 100% with John Cleese's comments.
In my opinion nowadays ITV have virtually given up on sitcoms whilst in their heyday in the 1960s and 1970s they were a conveyer belt for what are now seen as classic sitcoms such as Bless This House, On The Buses, Man About The House, Rising Damp, Please Sir!, George And Mildred and lots lots more.
Further evidence for me is that over the last five years I cannot think of one new sitcom that would make it into the 'classic category' and the BBC have even resorted to remaking a hit 1970s comedy in Reggie Perrin. In recent years the best sitcoms have been Still Game and The Green Green Grass, which are good but that is it - and don't get me started on My Family.