My name is Bob Rumson...and I'm running for President!
Gelbart doesn't see an agenda. He probably doesn't.
But, there is a liberal worldview conveyed in these pictures. All you have to do is watch a few movies, and it won't take you long to see who the good characters are, and who are the villains. Even in the comedies, the villains ultimately see the error of their ways, and they convert.
If you haven't seen Meet the Fockers, that's a perfect example. Look who the film shows as the characters we should be sympathetic to: a couple who arranged and approved of the maid boinking their adolescent son. They thought it would be a good first experience for him.
The good presidents are always liberal, but the corrupt ones are conservative.