The salient difference between comedy and what calls itself comedy nowadays (but is usually just irony) is this: comedy is loving. Today’s “comedy,” to the contrary, denigrates its object, ridicules it, encourages us to call it inferior.
The greatest practitioners of the former in the 20th c. are Laurel and Hardy; of the latter, George Carlin. We laugh at Laurel and Hardy — yes, they are dumb — but we love them nonetheless. Carlin hates the subjects of his monologues and encourages us to as well: the obese gluttons walking through the mall, etc. They are beneath him.
The temptation is that his masterful delivery persuades us to go along with him, as once I did. Then I realized what he was doing. No, thanks, not going to go there anymore. I’m sticking with Laurel & Hardy.