About 8. 9 if you count Peter Ustinov voicing a character in a Disney movie. Does that count? I think some of them were also on Law & Order.
I’m 67, and I recognize them all except for Charles Aznavour and Mummenschanz.
I do recollect hearing about the latter at one time or another but have no memory of who or what it was. A rock group, maybe?
From a quick scan of the list, I believe most do not recognize Kaye Ballard. She played one of the two titular characters on the NBC sitcom The Mothers-in-Law back in the '60s.
She’s the brunette.
Never mind, I just made a better scan and see I was a bit hasty in my judgment. 
And, her husband in the show, as shown in that clip, was played by Roger C. Carmel (Harry Mudd in Star Trek).
Who was that short, neighbor who was so nosy on a sitcom long ago?
Do you mean Mrs. Kravitz from Bewitched?
Recognized about 7 names. I’m 37. I never watched The Muppet Show and honestly would’ve been unlikely to recall the show ever existed in the first place. I primarily associate the Muppets with Sesame Street.
In which sitcom? The one above?
The blonde in that clip is, BTW, Eve Arden, aka Our Miss Brooks. She also had a memorable role alongside Joan Crawford in Mildred Pierce.
Our Miss Brooks also featured a very young Richard Crenna, John Rambo’s Col. Trautman.
Maybe the “short nosy neighbor” you’re thinking of is Don Knotts, aka Mr Furley on Three’s Company? He was also Andy Griffith’s deputy/sidekick Barney Fife on Andy’s sitcom.
That doesnt look like the actress. Sorry if Ive hijacked. Maybe it will come to me.
There were 2 Mrs. Kravitzes to make it tougher. Technically there was kind of a third, Abner’s sister came to help in a few episodes. She was a Miss Kravitz.
Alice Pearce, the first Mrs Kravitz, died from cancer during the second season of the show. She was replaced with Sandra Gould, who was never as funny. (Actually, I found her to be downright irritating.)
Alice Ghostly! Thats it. Thank you.
This for me as well.
16 out of the list, and I’m 60.
I also was not/am not a huge movie or tv watcher. There are a few more names I recognize, but I couldn’t tell you what they’d done.
Recognized 18.
Age 65.
I’ve heard of only 2 of these people. I knew the occupation of one of them, but I’m not familiar with their work and I don’t know what they look like. So, none for me.
I’m 42.
Now I’m curious: which two?
Phillis Diller: I recognize the name as a past media personality, probably actress or possible a tv journalist. Couldn’t pick her face out of a line up.
Twiggy: I recognize the name as a skinny model. I wouldn’t have been able to identify her among a group of other skinny models and until I just looked her up, would never have guessed her age. I would have been at least 2 decades off.
ETA: Oh, I missed Ben Vereen on that list. I know who he is.
20 of them.
I’m 66.