Oh come on! You know you can't compare cable and broadcast.Put Breaking Bad on broadcast and (even assuming they don't censor the hell out of it, which of course they would), it wouldn't get anything near survival-level ratings. There's a good reason that there are no shows like that on broadcast.
No one knows what kind of ratings it would get, because simply put, no one has put a show like it on network. Maybe NYPD Blue, with the language and the nudity come close. That lasted 10 years.
I think the networks are afraid to put something like that on, because they would get HAMMERED in the press by the Family Council for Blah Blah Blah, and they would neuter it, etc. Afraid of the FCC. Fear rules the executives...
But, what if they didn't? What would happen? Putting a show in a place that a LOT of people might find it? Who knows?
But yeah, Mad Men is boring. And it doesn't even get good ratings by cable standards. It would be a catastrophe on broadcast.
Actually, you're wrong there. it gets good ratings, even by cable standards, AND it also gets people watching who have a lot of disposable income, in other words, the best kind of audience.