Back then, there was actually competition, because there were only 2 other channels (with a possible exception of some local stations as well) where advertisers could sell their wares. That's no longer the case. There's not as much "exclusivity," and I think that shows in TV show development. Think about some of the "old time" shows that were on... While there were some real dogs, even they were pretty innovative. And the "good shows" were so much better than anything else on today.
For people who don't think so, I've got 2 " (not so) old time" shows to mention, and just TRY to come up with anything that's been on TV since that even come close:
The Tonight Show, with Johnny Carson. Yes, I know that it's still on, and while Jay Leno is good, NOBODY can come close to Johnny.
The Carol Burnett Show. `nuff said.
Mark