You’re right. Mad Men is 1960. As to the 1970s, I think this was a style struggling to come to terms with the changes that Franklin details. Here’s what she says in the EW review:

By 1976, some of the currents of the sixties–women’s liberation and youth culture–had become mainstream; family men sported long sideburns; schoolteachers looked a little more unbuttoned; mothers started wearing pants and shorter skirts, and going to work, and divorce had lost most of its shock value.

If we want, we can say this is a diffusion moment, when some of experimentation that took place in the 1960s enters the mainstream. The kids who made the 1960s were young, they were creatures of relative privilege, they had goodish educations. The people occupying the mainstream were hard working, nose to the grind stone, sexually conservative, religiously conservative, socially conservative and domestically conservative, and, bam, the world suddenly and fundamentally changed for them. (Yes, they had the opportunity of early notice. They got to see the 60s happening at a distance. But they were I think still tested.)

I think if popular culture “stank” it’s because it was bending before (or struggling to evade) the tectonic pressures of this culture shift. In the language of your distinquished book, it’s style giving voice to culture.

What I find curious is that while people seem to forget the junk of the 60s/80s/90s and remember the good stuff, the opposite is true of the 70s. It wasn’t that 70s pop culture was all bad, it’s just that the bad seems to be remembered more vividly than the good.

I was born in 1970 and grew up a kid of the 80s so I’m not in the best position to curate the pop cultural museum of the 70s, but I find plenty that I like from that decade (Philip K. Dick, Steely Dan, The French Connection, etc.) and many of my current heroes (Belle & Sebastian, Wes Anderson) clearly mine that decade for inspiration.

Also, here’s the Slate (positive) review of Swingtown:
http://www.slate.com/id/2193039/

I grew up in the era and have negative nostalgia for most pop culture from 1973-79, at least the parts I knew about (I didn’t discover things like Blondie until much later). James Lileks has very specific (and humorous)examples on his various websites of the outlandishly hideous and meretricious graphic design and artwork rife even in children’s books during this period.

It is not my impression that people who grew up in the 60s, ’80s, or ’90s have the same anti-nostalgia for the music, style, and pop culture of their youth. So perhaps we have an objective marker of sorts–no one is going to ever wear a rust-colored leisure suit again (unless as a form of campy drag) but skinny ties and ’80s music are genuinely enjoyed by those who grew up with them and those who grew up after them.

Just as we can judge literature by whether it stands the test of time, we can judge popular culture as well. Obviously, there is a normative value judgment at the bottom that can’t be derived from a more fundamental objective premise, but I’m pretty comfortable with a widely shared and deeply felt feeling of “yuck.” That judgment is a social fact at least as much as the demand curve for beer.