Lol, don't be such a snob! It may not be everybody's cup of tea, but it merits praise. I believe it started as a stage character of O'Carroll's 30 odd years ago, think of a pantomime dame, before it was picked up and transferred to tv. The setup, the occasional breaking of the 4th wall and with the crew and audience is novel for a sitcom too.
The scripts were clever, integrated a litany of classic jokes and phrases, well-written plots and engendered a sense of family and warmth.
But like everything, the pressure to keep churning out series after series takes its toll and the quality and new ideas reduces over time.