The key word on all those FCC pages is “broadcast”. Cable isn’t broadcast.
Here’s a cite from a decidedly biased source, Morality in Media:
Swearing is squarely in the “indecent material” camp. The FCC can block obscene material though, so I wasn’t correct when I said “there are no restrictions”. OTOH obscene material is essentially limited to hard-core porn, so you could show almost anything from HBO on basic cable without getting the FCC involved. They don’t because of the advertisers.