The death of Farrah Fawcett has caused a lot of people to write about TV in the late '70s (see Jim Henshaw's post for one of the beest examples) and what it was like. By "the late '70s," I tend to include 1980 and maybe even the early '80s, when there was a recession going on and the '70s air of despair and malaise (tm) was still being felt everywhere. TV was an escape from all that.
It was unquestionably more of a true mass-entertainment medium than it is now; the hit shows back then were watched by many more people than you get for most so-called hits today. The quality of writing and production was, overall, lower than TV today, with some exceptions (situation comedy was probably in better shape then than it is now).
But the most distinctive thing about the era was the style, a strange combination of several trends from earlier in the '70s. The early '70s had loosened network TV censorship a bit, while the mid-'70s tightened censorship again through the imposition of the Family Hour. The mid-to-late '70s was also a period when producers discovered that audiences' tastes actually hadn't changed very much (whereas in the early '70s, it was often assumed that audiences had become more "sophisticated"); this culminated in the success of the totally unsophisticated Star Wars, but it was a lesson Hollywood had been in the process of learning for several years.
So by the late '70s, network TV was able to say and show more than in the '60s, but it was aiming to be even more unsophisticated than TV of the '60s (which, given that that was the era of witches, genies and martians, is really saying something). The new freedom of the early '70s was still there, but it was now channeled into titillation, broad comedy, fantasy and action.
It was to television what Star Wars was to movies -- a rebuttal of everything anybody had ever said about the "maturing" of the audience. I say that to describe the era, not to put it down. A lot of these shows, like Star Wars, succeeded because they were very entertaining. More than that, they hold up better as entertainment and even as art (using the term loosely) than the television that critics claimed was Good For You. If it's a choice between Laverne and Shirley and Larry Gelbart's deliberately unfunny comedy United States, the former is much better written. But it was an era when series television was mostly very simple: simple storytelling, simple morality, simple characters.
It was also an un-ironic age of TV, when -- again, like Star Wars -- the most old-fashioned and silly plots would be trotted out and done without any self-mockery. It was the last era when a show could do, without any sense of humor whatsoever, a plot like this from the show Vega$: an evil hypnotist brainwashes the hero's dumb sidekick to kill the hero whenever he hears the trigger word "Superstar." In the '60s, this story would have been done tongue-in-cheek. In the 1979-80 season, it was played absolutely straight:
Even shows that aimed to be sophisticated had to incorporate those "unsophisticated" elements in order to succeed. And sometimes the need to be silly, flashy, and titillating actually improved a show. That's one thing I love about Taxi, that it takes the MTM style -- smart but often a little stolid -- and pumps it full of the things a show needed to be on ABC in the late '70s: broad, kid-friendly silliness (Latka), a beautiful woman who is inappropriately bra-less (Elaine), hunky young guys to keep the women watching (Bobby, Tony, probably not Randall Carver), and out-and-out fantasy (many episodes involving Latka or Jim). The mix of early '70s smart and late '70s goofy produced a great show. WKRP in Cincinnati, which can basically be described as The Mary Tyler Moore Show re-tooled to look like Three's Company, also has that appealing mix of styles.
And of course there was Soap, an "issue" comedy in the early '70s Norman Lear vein, written by the person who wrote the Maude abortion episodes for him, which got by in the late '70s by pumping itself full of titillation, goofiness, fantasy, etc. You literally could not do a smart show in 1977-8 if you weren't willing to make it look stupid, but the stupid elements probably helped make a smart show more interesting.
We'll never see the like of late '70s TV again, except in an ironic sort of way. On the whole, that's probably a good thing, but even a bad late '70s show can be strangely watchable. It was perhaps the last golden age of television showmanship, of scripted TV producers who would do anything to entertain us.