I can answer this; I have a brother who, in addition to being an engineer, also spent a couple of decades working in radio, both professionally and non-professionally.
Once upon a time, when the FCC reigned supreme over all broadcast media in the US, they had rather specific and pointed rules about what could and could not be said on the air, and pretty much brooked no argument, under pain of severe fines. See George Carlin's famous "Seven Words You Can't Say on TV" skit for a taste of what this regulation was like.
A number of things worked to undermine that authority over the years, from the Supreme Court's redefinition of "obscenity" to tie it to community standards, to corporate desire to possess more of the public airwaves, to the FCC itself being used as a political football in congressional disputes and disputes between the legislative versus the executive branches of government.
A lot of things resulted (the disappearance of the "Fairness Doctrine" being but one of them), but the overall effect was a more or less simultaneous blurring of the rules and an increase in the penalties for transgressing them. The FCC no longer maintains a list of prohibited words or phrases, but instead couches its regulation behind vague phrases like "offensive to community standards". However, the changing face of communications has made determining what, exactly, constitutes "the community" more and more difficult, as things like satellite radio and streaming internet feeds can send virtually any broadcast anywhere in the world -- including places in which the community standards may be very different from those of the community in which the broadcast actually originates.
This caused radio and TV stations to scramble to enact self-regulation, first to avoid hefty fines due to enforcement of ambiguous laws, and second, in the theory that if they sufficiently self-policed then they government wouldn't step in with even more draconian regulations than the old ones. Some have taken reasonable steps, such as making sexual and excretory references verboten
during certain hours (typically prior to 10pm), and forbidden after those hours only
if someone actually contacts the station to complain. This is really more or less the way the old regs were usually enforced, anyway.
Other stations have bent over backwards in an attempt to avoid even the appearance of offense to [i[anyone[/i] who might be listening or watching, which has -- predictably -- created an asinine situation. Teen listeners in NYC or East LA might be just fine with language or images that a minister listening in Muskogee might think is vile. 11pm on the east coast is still the middle of prime time on the west coast; etc.
In keeping with this insane attempt at absolute PC, many stations decided that, in addition to the traditional F-bomb and S-bomb, and similar sentiments, taking the Lord's name in vain
would be offensive to many Americans, and was thus to be avoided with the same diligence as references to unprotected 4n4l sex during prime time. But not all stations chose to enact such a regulation -- the FCC certainly doesn't require it -- and those that did didn't all enact it in the same way.
The classic example for me, was when Obama's opponents discovered the Rev. Wright, and stations began playing the now infamous excerpt from Wright's sermon in which he says, "Not God bless America; God DAMN America!"
Initially, many stations aired the excerpt unexpurgated -- probably for the shock value -- and even in the good old days "goddamn" wasn't a forbidden work on radio and TV, except withing a very narrow prime time window. But then, as the excerpt was repeated endlessly over days and weeks, some stations began to worry that they might be offending some people, and thus transgressing the vague FCC rules, each transgression of which could cost them $50K or more, in each
market they reached.
So on some stations, "God DAMN America!" became "[bleep] America!".
Other stations felt that this was counterproductive: by bleeping the entire "God DAMN", they might be encouraging listeners to think that an even more
offensive term had been deleted. Horrors! So they deleted the 'cuss word' part of the phrase, and came up with "God [bleep] America!"
Other stations felt that the real offense here was taking the Lord's name in vain, and reasoned that, even back in the 60s, and even during prime time, you could get away with saying "damn" now and they. So on their stations the comment was rendered as "[bleep] DAMN America!" And this is the approach still employed by some networks and stations.
So if George Carlin were doing his routine today, his "seven words you can't say" would be something like "shit, fuck, cock, cunt, cocksucker, motherfucker, and God." A bit ironic, that.
The vagueness of the FCC combined with heavy-handed enforcement has had other odd effects. For example, there is a fair amount of Spanish language programming locally. One station which would even consider allowing the English equivalents to air, has no problem with broadcasting "¡chingada!
" or "tu puta madre
". And I've heard more than one program in French liberally salted through with exclamations of "merde!
Apparently the assumption is that native Spanish and French speakers are not offended by the same things as native English speakers, and those who are multilingual are not offended by non-English renditions of words and phrases which would offend them if uttered in English. But mostly, it's probably due to ignorance.
As far as I'm concerned, it's all a bunch of gówno prawda