Chevy CHASE? HE'S funny?
Eddie Murphy isn't funny? Or, more accurately, Eddie Murphy was NEVER funny?
Martin Short wasn't funny?
Phil Hartman wasn't funny? The sketch in which Reagan orchestrated every last detail of Iran-Contra, even speaking fluent Arabic and Swedish, was the best political sketch of all time, and probably accurate. Second best was the sketch of Ross Perot dropping his VP candidate (whose name escapes me) off in the woods like an unwanted dog... "GRIDLOCK!!!" THIRD best was the most brutal bitch-slap of liberalism ever, "Dukakis After Dark," in which Willie Horton "dirty danced" with Donna Rice.
Julia Louise-Dreyfuss wasn't funny? I think she's probably the funniest woman alive.
Jan Hooks wasn't funny? Watch the Alamo sequence from Pee Wee's Big Adventure again - that was one of the best parodies ever filmed.
"Funny" is a subjective term, but I personally see a lot of exceptions to your statement.
You are almost correct. SNL was actually at its funniest shortly after Chase left, but then began a rather rapid descent when several others left for bigger and better things. SNL was at its very best when the "Not Ready for Primetime Players" consisted of:
Jane Curtin
Dan Ackroyd
Bill Murray
Lorraine Newman
John Belushi
Gilda Radner
Garrett Morris
I'll never forget the Weekend Update segments with Curtin and Ackroyd (their Point-Counterpoint was hysterical), the commentaries by Emily LaTella (Radner), and sports coverage by Manny "Baseball been berry-berry good to me" Mosa (Morris). Also, the Bad News Bees, the Samurai sketches, and other classics from Belushi were great.
When that ensemble broke up, SNL went straight into the toilet.