There's certainly something to novelty wearing off with time but I don't think that diminishes historical work. When I listen to Abbott and Costello perform "Who's on First?" (c. 1938) - it's still funny. It's not intrinsically less funny because I've heard it and things it inspired many times over.

It's also in how you watch things. I sometimes catch old films in the theatre and the room is filled with laughter. I was belly laughing to The Palm Beach Story (Sturges, 1942). Heck, I've been to see Shakespeare where everyone's laughing.