I have been rummaging through old celebrity roasts and I'd say don't sleep on Henny Youngman and Milton Berle, especially in a format that lets them get closer to the line than prime time standards would allow. I respect how these two guys could be suggestive without using dirty language. Years of honing their skill really show. They are pretty old in the few videos that still exist of them. Same for Groucho Marx. It's something Seinfeld talks about a lot in his 'Cars and Coffee' series, how to be suggestive without crossing lines. It's a rare skill and IMO shows a lot of respect to the audience. Pretty much anyone can go with dirty language to get laughs, it takes real skill to get a laugh via suggestion without using dirty language.
It's kind of amazing how raunchy things could get back then if the show was going to air after 11 pm. Even the Tonight Show stuff was raunchier than what we'd allow today.
There's some u2b videos that are audio-only renditions of the earlier Friars Club roasts presumably not televised with Johnny Carson that are absolutely raunchy. It's amazing how dirty he was when he wasn't needing to meet TV standards.