"... what he's pretending to do on screen"
I remember seeing this discussed around the show The Marvelous Mrs Maisel, which is about a midcentury NYC divorcee getting into the world of stand up comedy. Overall it works and is a funny and enjoyable show, but there's definitely some of the standup routines depicted on-screen that are not actually as funny as the baked-in audience laughs might indicate. Because yeah... you can't really fake delivering good standup, even with a whole writer's room preparing the jokes and all the editing magic in the world, you still have to actually stand there and tell them in a funny way. That part can't be faked.
I think I really loved Barry for exactly the opposite of this reason. Seeing a truly great actor play a bad actor was both impressive and hilarious at the same time.
Hacks does it fairly well, or it may just be jean smart
It never occurred to me that the jokes were oversold. I think the show is genuinely funny, with a very high batting average. Easily one of the funniest shows on television.
I sure do miss 'Mrs. Maisel'. What a stellar series.