I don't understand this phenomenon. I always liked Tim conway as a personality, but I also felt that he, Harvey Korman, and the whole Carol Burnett group were just not as naturally hilarious as some other comedians.
Comedy is like food. Everyone has different tastes. Also, they change. Things I wept with delirious laughter tears over 20 years ago I might not find as funny today. I think that a lot of the Carol Burnett skits were funnier because of Tim Conway and his drive to crack up his costars.
I always enjoyed the Carol Burnett show and recall skits where Korman would try to keep a straight face but start cracking up. Something about that just made it funnier to me. Korman was great in Blazing Saddles and History of the World Part I. And I remember Tim Conway and Don Knotts movies making me laugh when I was a kid. Not on par with other comedians, but good memories anyway.