The controversial actor/comedian did a stand-up set at MonDeRays at the Hollywood Improv Friday night where he shared his disappointment with Katt -- particularly outraged that his fellow comedian exclusively went after Black comedians.

DC said, "He ethered n*****. He didn't say anything about any of these white boys. None of these white boys function like that." Basically, Dave seems to be saying he's not seeing white comedians rake each other over the coals ... but Katt went after a whole lotta Black artists.

Chappelle added that "hurt people hurt people," but acknowledged he, himself, is also a hurt person ... and you don't see him throwing shade at his fellow comics.

He did defend a couple of Katt's targets -- specifically Cedric the Entertainer and Steve Harvey -- though both guys caught a couple strays in his defense.

CTE got it worse ... Chappelle said going after Cedric -- who Katt said was stealing jokes -- makes no sense because he's "old" and "fat" ... ya gotta think Cedric might be throwing a bit of side-eye at Dave for those adjectives.

As for SH, Dave said he shouldn't draw any ire because he's out of the stand-up game at this point -- focusing more on hosting TV shows like "Family Feud" and "Judge Steve Harvey."

Chappelle added his impersonation of Katt too -- full of profanity and a high-pitched voice -- before pointing out KW never really copped to anything he did ... instead choosing to focus on what other comedians did to one another.

Another big moment ... Dave rejected the claim what Katt did was good for comedy -- an argument comedian Deray Davis tried to make onstage -- saying quite simply that he put a special out the same day as the interview ... and it did fine.

If you haven't heard Williams' comments by now ... damn, there were a lot! He went after Cedric, Steve, Ludacris, Kevin Hart, Tiffany Haddish, Trick Daddy and a crap ton more -- some have responded to Katt while others have stayed quiet.