Not consistently funny since the mid-to-late 70’s, IMHO...
It was pretty good in the Eighties, too. It was never “consistently funny.” It was more hit or miss even when it was good. But it was something new back in the Seventies. Something different from the rest of television. So things that wouldn’t be that funny today got laughs back then because they were new. Beyond question, though, it got really bad in the new century.