The former Jerome Silberstein has basically been retired from acting for the past twenty years. As he has told several interviewers in recent years, "I don't like show business. I like show! I just don't like the business."
related: Ten Retired Film Stars Who Deserve A Comeback. Also, a Brooks-Wilder anecdote I feel compelled to add, below the fold:
Brooks, 2010: "I was in the middle of shooting the last few weeks of "Blazing Saddles" somewhere in the Antelope Valley, and Gene Wilder and I were having a cup of coffee and he said, I have this idea that there could be another "Frankenstein." I said not another – we've had the son of, the cousin of, the brother-in-law, we don't need another Frankenstein. His idea was very simple: What if the grandson of Dr. Frankenstein wanted nothing to do with the family whatsoever. He was ashamed of those wackos. I said, "That's funny."
"The biggest fight we had, honestly, shame on me, was he said to prove the monster was more than mechanically able to walk or move, he wanted the monster to do Irving Berlin's "Putting on the Ritz." I said, "Having the monster sing and dance is just going to be silly." He said maybe you're right, but can we try it? So we shot it and I said, "This is the best thing in the movie.""