The point is, it's not having a go at the people being talked about as "queer." It's having a go at the bigoted old men and, by extension, those of similar views for (a) making prejudiced assumptions about those who happen to be in the media (b) thinking there is something wrong in being homosexual, as is implicit in their sneering tones, and usage of the pejorative, 'queer,' to describe gays.
Having said that, while the 'He's on telly, he must be queer' phrase might be funny as a throwaway line, continually repeating it makes for a repetitive and not funny sketch, in my opinion.