I've been thinking about this ever since I had to admit to never having watched Trainspotting from beginning to end.
One of the embarrassments of being Canadian in the UK is watching UK television with my visiting Canadian parents. British comics will say almost anything on television, and I thank heaven my mother was not there when Frankie Boyle made his infamous remark about the Queen; do not google this or you will be sorry. There can be full frontal nudity after 9 PM. The reality "medical" show Embarrassing Bodies must be a voyeur's dream. Silent Witness features the sad dead breasts of murdered corpses. Its stars solemnly lift out livers and saw through skulls. What Canadians and Americans call "bathroom humour" appears in Scotland's beloved comedy show Still Game.
On British television, the F word is king and the S word is crown prince, and the only guardians of good taste are the fears of appearing sexist, racist, cruel to children, cruel to the disabled or Islamophobic. Possibly you can be mean about animals although I don't recall any comedian being snide about them or blurting out "F*** sweet little dogs. F*** them and eat them with a spoon!" This may have been said, of course.
Bad language is so common on British television (especially after 9 PM) and in British films, that it is remarkable that most ordinary people in Scotland do not speak like that on the bus or on the street unless absentmindedly into their mobile phones. Some do speak like that to the pal beside them but not to strangers. Overhearing a live woman drop the F bomb is so rare that I still remember the woman who dropped it while shopping in British Home Stores on Princes Street. I have much more often overheard Polish women drop the Polish equivalent in their bus-time conversations.
Curious. I think the sexes in Scotland strive not to use bad language before the other sex, in general, but I may be wrong about this. At any rate, a Scot considers wrong to use it before strangers unless she/he is drunk, feels offended and is kicking off, in which case she/he probably thinks (EXTREME VIOLENCE BY DRUNKEN WOMAN ALERT) anything goes.
Lest I singlehandedly destroy Edinburgh's tourist economy, I should hasten to say that the linked-to story is the worst drunken-Edinburgher-kicking-off story I have ever heard.