Johnny Carson had ten times the audience of Jay Leno. Now Jimmy Fallon has even a smaller audience.
Carson wasn’t necessary better; he just had more attention when there were only four stations to choose from.
Tribes are smaller now. Back then you had a bigger audience but with only a few microphones. Now everyone has a microphone (Facebook, Twitter, Blogs). Now we can communicate, assemble the tribe, and share a connection. Now we have choices which puts pressure on those that produce the work to level up.