Since it was based on Carl Reiner’s previous life as a comedy writer for Sid Caesar it was more based on him. Reiner himself said Brady was based on other demanding comedy stars of the time. Alan Brady was not supposed to be Carl Reiner.
Exactly. Rob Petrie was supposed to be Carl Reiner (so much so that in the original pilot, he played the role himself). Alan Brady was Sid Caesar, Buddy was Mel Brooks, and Sally was a combination of Selma Diamond and Lucille Kallen.
Howzabout Gary Shandling in “It’s Gary Shandling’s Show?”
Doesn’t Bill Murray play “himself” in Zombieland?
Tig Notaro and Sarah Silverman play themselves in a (very funny) episode of Maria Bamford’s Lady Dynamite."
Gaten Matarazzo (Dustin from “Stranger Things”) plays a rich douche version of himself in “The Legend of Foggy Mountain”.
James van der Beek played himself in Don’t Trust the B---- Apartment 23 as an egotistical jerk. It played upon his image from Dawson’s Creek.
Jennifer Grey played a version of herself in It’s Like . . . You Know. There were even jokes abour her disasterous nose job.
I don’t think I saw that episode, or if I did I don’t remember (I watched season 1 but I think there were two seasons). But speaking of Sarah Silverman, she played a very selfish, narcissistic version of herself on ‘The Sarah Silverman Program’.
I recall Felicia Day in interviews saying that she wrote a lot of herself into Codex on The Guild as she was also once an MMO addict coping with depression and social anxiety.
If anything that was a better version of himself.
Funniest scene in that movie!
“I can’t even lurk anymore!” and “I promise!” 
Does that mean Ritchie was Rob Reiner?
One that hasn’t been mentioned is Keanu Reeves playing himself in Always Be My Maybe.
Also mentioned in posts 5 & 6.
In CANNONBALL RUN, Roger Moore — who, when he played James Bond, wore a tuxedo and brandished a gun and drove a fast car — wore a tuxedo and brandished a gun and drove a fast car and called himself Roger Moore.
I may be doing this wrong.
George Takei played a rather easily befuddled version of himself on the show Psych during the first season “Shawn vs. the Red Phantom” . The protagonists manage to become his assistants without him realizing they aren’t. This happens at a Comic Book convention which would be a real life situation he would actually involved in, and he is listed in the credits as himself.
I remember watching it and finding it especially funny because I recognized him right away, something others in my family did not.
//i\\
In the show Roswell Jonathan Frakes is the celebrity guest at a UFO convention. He plays an entitled douchey version of himself. I believe he was uncredited as an actor but he was also executive producer and directed several episodes of the show.
Matt LeBlanc in Episodes played a smug, vain, fame-obsessed version of himself.
David Bowie in Extras was gloriously vicious to Ricky Gervais’s character, capped off by his spontaneous “little fat man” song. Very funny.
never mind - additional commentary at this point would be superfluous
There’s a current series of commercials for some credit card in which Kristen Bell plays an insufferable, comically entitled version of herself.