Sounds like trying to prove a negative. If people want to convince me that cancellation is a real thing for comedians, I'd want to see...examples of comedians who actually got cancelled. CK and Chappelle ain't it.
I have an inkling of how this would go. I'd do a quick google search and offer up a handful of names. The counter argument would probably be along the lines of 'that wasn't really cancellation, it was actually...' and then we'd go back and forth debating the meaning of words.
The point I was specifically trying to make was that because Chapelle defied expectations and was successful, that does not mean cancellation isn't a real thing that can happen to other comedians.