As a Teenager, I Hated Johnny Carson. Then Came the Pandemic
nytimes.com
nytimes.com
That said, having seen him dress down Uri Gheller, he has my admiration.
[1] He was not an exception in the US or in the world. There are comedians in the modern world whose society is more like the US in the 1970s in terms of social mores. I can see blaming them if they are aware of progress, but not if they are so imbued in local culture and customs that they know no better. Same for Carson back then. I think it’s forgivable. The same people complaining would very likely have behaved equivalently in that time.