What Was I Thinking? Don Rickles

I watched an HBO special on Don Rickles last night. I was looking for a good laugh. It was directed by John Landis and it was done with all kinds of editing flourishes. The bottom line, "Why is this guy considered a comic genius?" I laughed at him back in the 60's and 70's etc with my father, especially when Rickles was on the tonight show. But the insult act is so tired and his rationalizations so bogus. It's one thing to "shoot down" a Sinatra and the rich and powerful and pretentious, but not a Mexican immigrant.
Compare him to the timeless comic genius of a Steve Allen and a Sid Caesar, not a chance. Ok, I'm thru pontificating.
Now the above clip I find funny, Rowan And Martin roasting Rickles with his own material